Retractable vehicle step

ABSTRACT

A retractable step for use with a vehicle comprises a stepping member having a stepping deck, a first arm, a second arm, a motor and a stop. The first arm has a first end pivotally attached to the vehicle, and a second end pivotally attached to the stepping member. The second arm also has a first end pivotally attached to the vehicle, and a second end pivotally attached to the stepping member. The motor is drivingly connected to the first arm such that a rotation of the motor causes rotation of the first arm about its first end and moves the stepping member from a retracted position to an extended position, or vice versa. The stop is located within the range of motion of the second arm such that the second arm bears against the stop when the stepping member is in the extended position. The first and second arms are situated such that the first arm is loaded in compression and the second arm is loaded in tension when the stepping member is in the extended position and a load is placed upon it. In another embodiment, a retractable vehicle step assist comprises a rigid frame, a forward planar linkage pivotably connected to the frame along a forward upper connection width, and a rearward planar linkage pivotably connected to the frame along a rearward upper connection width. The retractable vehicle step further comprises a rigid step member having a stepping deck. The step member is pivotably connected to the forward planar linkage along a forward lower connection width, and is pivotably connected to the rearward planar linkage along a rearward lower connection width and on a side of the forward planar linkage opposite the stepping deck. The stepping deck is substantially wider than any of the forward upper connection width, the rearward upper connection width, the forward lower connection width, and the rearward lower connection width.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.10/274,418, filed Oct. 16, 2002 now U.S. Pat. No. 6,834,875, titledRETRACTABLE VEHICLE STEP, which claims the benefit of U.S. ProvisionalPatent Application Ser. No. 60/350,129, filed Oct. 16, 2001, titledRETRACTABLE VEHICLE STEP, and of U.S. Provisional Patent ApplicationSer. No. 60/404,353, filed Aug. 15, 2002, titled RETRACTABLE VEHICLESTEP. The entire contents of the above-mentioned patent applications andeach of the above-mentioned provisional patent applications are herebyincorporated by reference herein and made a part of this specification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to a stepping assist for motorvehicles. In particular, the invention relates to a retractable vehiclestep which is movable between a retracted or storage position and anextended position in which it functions as a step assist into thevehicle.

2. Description of the Related Art

It is commonly known to add a running board or similar fixed steppingassist to the side of a motor vehicle, especially to a vehicle with arelatively high ground clearance. However, these fixed running boardsand other stepping assists have had several drawbacks. First, a fixedrunning board is often too high to act as a practical stepping assistand is therefore not very effective in reducing the initial step heightfor the vehicle user. In addition, when using a relatively high runningboard, the user is likely to hit his or her head while climbing into thevehicle cab. Furthermore, a fixed running board often extends asignificant distance from the side of the vehicle, and can be a sourceof dirt or grime that rubs onto the user's pants or other clothing asthe user steps out of the vehicle onto the ground surface. Such a fixedrunning board is also frequently struck when the owner of an adjacentparked vehicle opens his door. Finally, a fixed running board or stepreduces the ground clearance of a vehicle, and can often be damaged ortorn off entirely when the vehicle is used for offroad driving.

Accordingly, a vehicle step which overcomes the above-stated problems isdesired.

SUMMARY OF THE INVENTION

In accordance with one embodiment, a retractable step for use with avehicle comprises a stepping member having a stepping deck, a first arm,a second arm, a motor and a stop. The first arm has a first endpivotally attached to the vehicle, and a second end pivotally attachedto the stepping member. The second arm also has a first end pivotallyattached to the vehicle, and a second end pivotally attached to thestepping member. The motor is drivingly connected to the first arm suchthat a rotation of the motor causes rotation of the first arm about itsfirst end and moves the stepping member from a retracted position to anextended position, or vice versa. The stop is located within the rangeof motion of the second arm such that the second arm bears against thestop when the stepping member is in the extended position. The first andsecond arms are situated such that the first arm is loaded incompression and the second arm is loaded in tension when the steppingmember is in the extended position and a load is placed upon it.

In accordance with another embodiment, a retractable vehicle step assistcomprises a rigid frame, a forward planar linkage pivotably connected tothe frame along a forward upper connection width, and a rearward planarlinkage pivotably connected to the frame along a rearward upperconnection width. The retractable vehicle step further comprises a rigidstep member having a stepping deck. The step member is pivotablyconnected to the forward planar linkage along a forward lower connectionwidth, and is pivotably connected to the rearward planar linkage along arearward lower connection width and on a side of the forward planarlinkage opposite the stepping deck. The stepping deck is substantiallywider than any of the forward upper connection width, the rearward upperconnection width, the forward lower connection width, and the rearwardlower connection width.

In accordance with yet another embodiment a retractable vehicle stepassist for use with a vehicle having two adjacent doors through whichpersons may enter the vehicle, comprises a rigid frame, a step memberhaving a stepping deck, and at least two rigid arms connecting the stepmember to the frame and allowing the step member to move between aretracted position near the frame to a deployed position downward andaway from the frame. The stepping deck is of sufficient width to providea step for persons desiring to enter either of the doors.

In accordance with still another embodiment, a retractable vehicle stepassist for use with a vehicle having two adjacent doors through whichpersons may enter the vehicle, comprises a rigid frame and a step memberhaving a stepping deck. The retractable step assist further comprises atleast two rigid arms connecting the step member to the frame andallowing the step member to move between a retracted position near theframe to a deployed position downward and away from the frame. Thestepping deck extends in front of each of the doors when in the deployedposition.

In accordance with still another embodiment, a retractable vehicle stepassist comprises a rigid frame, a step member having a stepping deck,and at least two rigid arms connecting the step member to the frame andallowing the step member to move between a retracted position near theframe to a deployed position downward and away from the frame. Thestepping deck is substantially wider than the frame.

In accordance with still another embodiment, a retractable vehicle stepassist comprises a rigid frame, a step member having a stepping deck,and a forward rigid arm and a rearward rigid arm connecting the stepmember to the frame and allowing the step member to move between aretracted position near the frame to a deployed position downward andaway from the frame. The step member is pivotably connected to therearward rigid arm at a rearward pivotable connection and the stepmember rotates downward about the rearward pivotable connection as thestep member moves to the deployed position.

In accordance with still another embodiment, a retractable vehicle stepassist comprises a rigid frame, a step member having a stepping deck,and at least two rigid arms connecting the step member to the frame andallowing the step member to move between a retracted position near theframe to a deployed position downward and away from the frame. Thestepping member further comprises a support bracket rigidly connected tothe stepping deck and connected to the arms opposite the stepping deck.The support bracket is oriented at an angle to the stepping deck.

In accordance with still another embodiment, a method of improvingaccess to a vehicle through a door of the vehicle, comprises attaching arigid frame to the vehicle, and connecting a stepping member having astepping deck to the frame via at least two rigid arms. This is done sothat the stepping member is moveable between a retracted position nearthe frame to a deployed position wherein the stepping deck is situatedalong the side of the vehicle below the door. In the method the steppingdeck is substantially wider than the frame.

In accordance with another embodiment, there is provided a retractablestep for a vehicle having a body with a lower edge. The step comprises arigid frame configured for attachment to the vehicle so thatsubstantially all of the frame is behind the lower edge of the body, arotatable linkage connected to the frame, and a step member connected tothe rotatable linkage opposite the frame. The step member has a deployedposition, and a retracted position in which the step member and therotatable linkage are located behind the lower edge of the body.

In accordance with another embodiment, there is provided a vehicle whichcomprises a body having a lower edge and a retractable step assistattached to the vehicle. The retractable step assist comprises a rigidframe attached to the vehicle so that substantially all of the frame isbehind the lower edge of the body, a rotatable linkage connected to theframe, and a step member connected to the rotatable linkage opposite theframe. The step member has a deployed position, and a retracted positionin which the step member and the rotatable linkage are located behindthe lower edge of the body.

In accordance with another embodiment, there is provided a retractablevehicle step assist configured for attachment to a vehicle. The stepassist comprises a rigid frame, a step member having a stepping deck,and a rotatable linkage. The linkage connects the step member to theframe and allows the step member to move between a deployed position anda retracted position in which an upper surface of the stepping deck issubstantially concealed from the view of an adult standing outside thevehicle.

In accordance with another embodiment, there is provided a retractablestep for a vehicle having a body with an under panel. The step comprisesa rigid frame configured for attachment to the vehicle, a rotatablelinkage connected to the frame and a step member connected to therotatable linkage opposite the frame. The step member has a steppingdeck with an upper surface. The step member has a deployed position, anda retracted position in which the upper surface of the stepping deck issubstantially flush with the under panel.

In accordance with another embodiment, there is provided a retractablevehicle step assist configured for attachment to a vehicle. The stepassist comprises a rigid frame, a step member having a stepping deck,and a rotatable linkage. The linkage connects the step member to theframe and allows the step member to move between a deployed position anda retracted position in which only a forward edge of the stepping deckis visible to an adult standing outside the vehicle.

In accordance with another embodiment, there is provided a retractablestep for a vehicle having an underbody with a substantially verticalouter surface. The step comprises a rigid frame configured forattachment to the vehicle, a linkage connected to the frame, and a stepmember connected to the linkage opposite the frame. The step member hasa deployed position, and a retracted position in which a forward edge ofthe step member is spaced rearward from the outer surface of theunderbody by at least 1.5 inches.

In accordance with another embodiment, there is provided a retractablestep for a vehicle having a body with a lower edge. The step comprises arotatable linkage connectable to the vehicle, and a step memberconnected to the rotatable linkage. The step member has a deployedposition, and a retracted position in which the step member and therotatable linkage are located behind the lower edge of the body.

In accordance with another embodiment, there is provided a vehicle,comprising a body having a lower edge, and a retractable step assistattached to the vehicle. The retractable step assist comprises arotatable linkage connected to the vehicle, and a step member connectedto the rotatable linkage. The step member has a deployed position, and aretracted position in which the step member and the rotatable linkageare located behind the lower edge of the body.

In accordance with another embodiment, there is provided a retractablestep for a vehicle having an underbody with a substantially verticalouter surface. The step comprises a linkage connectable to the vehicle,and a step member connected to the linkage. The step member has adeployed position, and a retracted position in which a forward edge ofthe step member is spaced rearward from the outer surface of theunderbody by at least 1.5 inches.

In accordance with another embodiment, a retractable step for a vehiclecomprises a forward linkage having an upper portion connectable to thevehicle so as to be rotatable about a first axis, and a rearward linkagehaving an upper portion connectable to the vehicle so as to be rotatableabout a second axis. The second axis is located rearward of the firstaxis, and the first and second axes are oriented generally parallel to alongitudinal axis of the vehicle. The step further comprises a stepmember connected to the forward and rearward linkage so as to be movablebetween a retracted position and an extended position. At least aportion of the rearward linkage extends forward of the first axis whenthe step member is in the extended position.

In accordance with another embodiment, a retractable step for a vehiclecomprises a first arm having an upper portion rotatably fixable withrespect to an underside of the vehicle so as to be rotatable about afirst axis of rotation oriented generally parallel to an adjacent loweredge of the vehicle. The step further comprises a second arm having anupper portion rotatably fixable with respect to an underside of thevehicle so as to be rotatable about a second axis of rotation orientedgenerally parallel to an adjacent lower edge of the vehicle and locatedrearward of the first axis. The step further comprises a step memberconnected to the first and second arms so as to be movable between aretracted position near the underside of the vehicle and an extendedposition remote from the underside. At least a portion of the second armextends forward of the first axis when the step member is in theextended position.

In accordance with another embodiment, a retractable step for a vehiclecomprises a first arm having an upper portion rotatably fixable withrespect to an underside of the vehicle so as to be rotatable about afirst axis of rotation, and a second arm having an upper portionrotatably fixable with respect to an underside of the vehicle so as tobe rotatable about a second axis of rotation. The step further comprisesa step member connected to the first and second arms so as to be movablebetween a retracted position under the vehicle and an extended positionextending outward from the vehicle. At least one of the first arm andthe second arm further comprises a stop member which extends toward theother of the first arm and the second arm and contacts the other armwhen the step member is in the extended position.

In accordance with another embodiment, a retractable step for a vehiclecomprises a first arm having an upper portion rotatably mountable to anunderside of the vehicle so as to be rotatable about a first axis ofrotation oriented generally parallel to an adjacent lower edge of thevehicle, and a second arm having an upper portion rotatably mountable toan underside of the vehicle so as to be rotatable about a second axis ofrotation oriented generally parallel to an adjacent lower edge of thevehicle and located rearward of the first axis. The step furthercomprises a step member connected to the first and second arms so as tobe movable between a retracted position at least substantially entirelyunder the vehicle and an extended position extending outward from thevehicle. The step member comprises a stepping deck defining an uppersurface thereof and a connection region which is located rearward andupward from the stepping deck when the step member is in the extendedposition, and wherein at least one of the first and second arms isconnected to the step member at the connection region. It is believedthat this overall arrangement facilitates storing the step out of sight,while enabling the final deployment movement of the step to include adownward rotational component about a third axis at the lower end of thefirst arm. It is believed that this arrangement facilitatesself-energizing of the step. That is, when a load is placed on the step,the step continues its downward rotational movement somewhat, so thatthe load is not carried by any motor driving the step.

In accordance with another embodiment, a retractable step for a vehiclecomprises a first arm having an upper portion rotatably mountable to anunderside of the vehicle so as to be rotatable about a first axis ofrotation, and a second arm having an upper portion rotatably mountableto an underside of the vehicle so as to be rotatable about a second axisof rotation oriented generally parallel to the first axis. The stepfurther comprises a step member connected to the first and second armsso as to be movable between a retracted position at least substantiallyentirely under the vehicle and an extended position extending outwardfrom the vehicle. The first arm is connected to the step member so as tobe rotatable about a third axis and the second arm is connected to thestep member so as to be rotatable about a fourth axis, the third andfourth axes being oriented generally parallel to the first and secondaxes. Desirably, the distance between the third and fourth axes is lessthan 6 inches, more desirably less than 4 inches and, most desirably,less than 2 inches. The axes are arranged according to a first aspectratio, which comprises a ratio of (1) the distance between the thirdaxis and the fourth axis and (2) the distance between the first axis andthe third axis, and the first aspect ratio is less than 0.4 and,preferably, less than 0.3. It is believed that these distances andratios facilitate the ability to permit the step to be stored in a smallenvelope out of sight and to yet be deployable to the desired deploymentposition.

In accordance with another embodiment, a retractable vehicle step assistcomprises a rigid frame, a forward planar linkage pivotably connected tothe frame along a forward upper connection width, and a rearward planarlinkage pivotably connected to the frame along a rearward upperconnection width. The step further comprises a rigid step member havinga stepping deck. The step member is pivotably connected to the forwardplanar linkage along a forward lower connection width, and pivotablyconnected to the rearward planar linkage along a rearward lowerconnection width and on a side of the forward planar linkage oppositethe stepping deck. The stepping deck is substantially wider than any ofthe forward upper connection width, the rearward upper connection width,the forward lower connection width, and the rearward lower connectionwidth.

In accordance with another embodiment, a retractable vehicle step assistfor use with a vehicle having two adjacent doors through which personsmay enter the vehicle, comprises a rigid frame, and a step member havinga stepping deck. The step assist further comprises at least two rigidarms connecting the step member to the frame and allowing the stepmember to move between a retracted position near the frame to a deployedposition downward and away from the frame. The stepping deck is ofsufficient width to provide a step for persons desiring to enter eitherof the doors.

In accordance with another embodiment, a retractable vehicle step assistfor use with a vehicle having two adjacent doors through which personsmay enter the vehicle, comprises a rigid frame, and a step member havinga stepping deck. The step further comprises at least two rigid armsconnecting the step member to the frame and allowing the step member tomove between a retracted position near the frame to a deployed positiondownward and away from the frame. The stepping deck extends in front ofeach of the doors when in the deployed position.

In accordance with another embodiment, a retractable vehicle step assistcomprises a rigid frame, a step member having a stepping deck, and atleast two rigid arms connecting the step member to the frame andallowing the step member to move between a retracted position near theframe to a deployed position downward and away from the frame. Thestepping deck is substantially wider than the frame.

In accordance with another embodiment, a retractable vehicle step assistcomprises a rigid frame, and a step member having a stepping deck. Thestep further comprises a forward rigid arm and a rearward rigid armconnecting the step member to the frame and allowing the step member tomove between a retracted position near the frame to a deployed positiondownward and away from the frame. The step member is pivotably connectedto the rearward rigid arm at a rearward pivotable connection and thestep member rotates downward about the rearward pivotable connection asthe step member moves to the deployed position.

In accordance with another embodiment, a retractable vehicle step assistcomprises a rigid frame, a step member having a stepping deck, and atleast two rigid arms connecting the step member to the frame andallowing the step member to move between a retracted position near theframe to a deployed position downward and away from the frame. Thestepping member further comprises a support bracket rigidly connected tothe stepping deck and connected to the arms opposite the stepping deck,the support bracket being oriented at an angle to the stepping deck.

In accordance with another embodiment, a method of improving access to avehicle through a door of the vehicle, comprises attaching a rigid frameto the vehicle, connecting a stepping member having a stepping deck tothe frame via at least two rigid arms so that the stepping member ismoveable between a retracted position near the frame to a deployedposition wherein the stepping deck is situated along the side of thevehicle below the door. The stepping deck is substantially wider thanthe frame.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first unitary support arm defining an inboard surface and anoutboard surface. A maximum distance between the inboard surface and theoutboard surface defines a first thickness, and the first arm defines asubstantially vertical first side and a substantially vertical secondside. A maximum distance between the first side and the second sidedefines a first width, and the first width is substantially greater thanthe first thickness. The retractable vehicle step assist furthercomprises a second unitary support arm defining an inboard surface andan outboard surface. A maximum distance between the inboard surface andthe outboard surface defines a second thickness, and the second armdefines a substantially vertical first side and a substantially verticalsecond side. A maximum distance between the first side and the secondside defines a second width, and the second width is substantiallygreater than the second thickness. The first support arm and the secondsupport arm are connectable with respect to an underside of a vehicle soas to be pivotable about a first axis oriented generally parallel to theground and a second axis oriented generally parallel to the ground,respectively. The retractable vehicle step further comprises a staticstop member located within a range of motion of one of the first supportarm and the second support arm. The retractable vehicle step furthercomprises a step member having a support bracket and a stepping deckrigidly connected to the support bracket. The stepping deck has an uppersurface, and the first support arm and the second support arm areconnected to the support bracket opposite the stepping deck so that thefirst support arm and the second support arm are pivotable with respectto the step member about a third axis and a fourth axis, respectively.The fourth axis is located inboard from the third axis. The first axisis spaced from the third axis by a first distance, the second axis isspaced from the fourth axis by a second distance, the first axis isspaced from the second axis by a third distance, and the third axis isspaced from the fourth axis by a fourth distance, as the step assist isviewed in a plane perpendicular to said first axis, and the thirddistance and the fourth distance are unequal. The first support arm andthe second support arm allow the step member and the stepping deck tomove between a retracted position and a deployed position downward andoutboard from the retracted position. When the step member is in thedeployed position, the support bracket extends inboard and upward fromthe stepping deck and the upper surface of the stepping deck is theuppermost portion of the step member outboard of the support bracket.The entirety of the stepping deck is located outboard of the first axiswhen the step member is in the deployed position and at least a portionof the stepping deck is located inboard of the second axis when the stepmember is in the retracted position. The static stop member, the firstsupport arm, the second support arm and the step member are sufficientto maintain the stepping deck in the deployed position when a user stepsonto the stepping deck. In a further embodiment, the first distance andthe second distance may be unequal.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first unitary support arm defining an inboard surface and anoutboard surface. A maximum distance between the inboard surface and theoutboard surface defines a first thickness, and the first arm defines asubstantially vertical first side and a substantially vertical secondside. A maximum distance between the first side and the second sidedefines a first width, and the first width is substantially greater thanthe first thickness. The retractable vehicle step assist furthercomprises a second unitary support arm defining an inboard surface andan outboard surface. A maximum distance between the inboard surface andthe outboard surface defines a second thickness, and the second armdefines a substantially vertical first side and a substantially verticalsecond side. A maximum distance between the first side and the secondside defines a second width, and the second width is substantiallygreater than the second thickness. The first support arm and the secondsupport arm are connectable with respect to an underside of a vehicle soas to be pivotable about a first axis oriented generally parallel to theground and a second axis oriented generally parallel to the ground,respectively. The retractable vehicle step further comprises a staticstop member located within a range of motion of one of the first supportarm and the second support arm. The retractable vehicle step furthercomprises a step member having a support bracket and a stepping deckrigidly connected to the support bracket. The stepping deck has an uppersurface, and the first support arm and the second support arm areconnected to the support bracket opposite the stepping deck so that thefirst support arm and the second support arm are pivotable with respectto the step member about a third axis and a fourth axis, respectively.The fourth axis is located inboard from the third axis. The first axisis spaced from the third axis by a first distance, the second axis isspaced from the fourth axis by a second distance, the first axis isspaced from the second axis by a third distance, and the third axis isspaced from the fourth axis by a fourth distance, as the step assist isviewed in a plane perpendicular to said first axis, and the thirddistance and the fourth distance are unequal. The first support arm andthe second support arm allow the step member and the stepping deck tomove between a retracted position and a deployed position downward andoutboard from the retracted position. The static stop member, the firstsupport arm, the second support arm and the step member are sufficientto maintain the stepping deck in the deployed position when a user stepsonto the stepping deck. In a further embodiment, the first distance andthe second distance may be unequal. In a further embodiment, theentirety of the stepping deck is located outboard of the first axis whenthe step member is in the deployed position and at least a portion ofthe stepping deck is located inboard of the second axis when the stepmember is in the retracted position.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first support arm and a second support arm. The firstsupport arm and the second support arm are connectable with respect toan underside of a vehicle so as to be pivotable about a first axisoriented generally parallel to the ground and a second axis orientedgenerally parallel to the ground, respectively. The step assist furthercomprises a step member having a support bracket and a stepping deckrigidly connected to the support bracket. The first support arm and thesecond support arm are connected to the support bracket opposite thestepping deck so that the first support arm and the second support armare pivotable with respect to the step member about a third axis and afourth axis, respectively. The fourth axis is located inboard from thethird axis. The first support arm and the second support arm allow thestep member and the stepping deck to move between a retracted positionand a deployed position downward and outboard from the retractedposition. The first support arm has an upper portion and a lower portioninterconnected by an intermediate portion. The intermediate portion isthinner than at least one of the upper portion and the lower portion,and is located such that the support arms can rotate about the first andsecond axes to a point at which a portion of the second support arm isspaced from a line connecting the first and third axes by an orthogonaldistance less than half the maximum thickness of the first support arm.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first support arm and a second support arm. The firstsupport arm and the second support arm are connectable with respect toan underside of a vehicle so as to be pivotable about a first axisoriented generally parallel to the ground and a second axis orientedgenerally parallel to the ground, respectively. The step assist furthercomprises a step member having a support bracket and a stepping deckrigidly connected to the support bracket. The first support arm and thesecond support arm are connected to the support bracket opposite thestepping deck so that the first support arm and the second support armare pivotable with respect to the step member about a third axis and afourth axis, respectively. The fourth axis is located inboard from thethird axis. The first support arm and the second support arm allow thestep member and the stepping deck to move between a retracted positionand a deployed position downward and outboard from the retractedposition. The first support arm has an upper portion and a lower portioninterconnected by an intermediate portion. The intermediate portion isthinner than the at least one of the upper portion and the lowerportion. The intermediate portion contacts the second support arm whenthe step member is in at least one of the retracted position and thedeployed position.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first support arm and a second support arm. The firstsupport arm and the second support arm are connectable with respect toan underside of a vehicle so as to be pivotable about a first axisoriented generally parallel to the ground and a second axis orientedgenerally parallel to the ground, respectively. The step assist furthercomprises a step member having a support bracket and a stepping deckrigidly connected to the support bracket. The first support arm and thesecond support arm are connected to the support bracket opposite thestepping deck so that the first support arm and the second support armare pivotable with respect to the step member about a third axis and afourth axis, respectively. The fourth axis is located inboard from thethird axis. The first support arm and the second support arm allow thestep member and the stepping deck to move between a retracted positionand a deployed position downward and outboard from the retractedposition. The first and second arms have a bent configuration such thatthe arms can rotate about the first and second axes to a point at whicha line connecting the first and third axes intersects a portion of thesecond arm near the second axis.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first support arm and a second support arm. The firstsupport arm and the second support arm are connectable with respect toan underside of a vehicle so as to be pivotable about a first axisoriented generally parallel to the ground and a second axis orientedgenerally parallel to the ground, respectively. The step assist furthercomprises a step member having a support bracket and a stepping deckrigidly connected to the support bracket. The first support arm and thesecond support arm are connected to the support bracket opposite thestepping deck so that the first support arm and the second support armare pivotable with respect to the step member about a third axis and afourth axis, respectively. The fourth axis is located inboard from thethird axis. The first support arm and the second support arm allow thestep member and the stepping deck to move between a retracted positionand a deployed position downward and outboard from the retractedposition. At least a portion of the stepping deck is located above thefirst axis when the stepping deck is in the retracted position. Thefirst axis is spaced from the third axis by a first distance, and thesecond axis is spaced from the fourth axis by a second distance, as thestep assist is viewed in a plane perpendicular to said first axis, andthe first distance and the second distance are unequal.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first support arm and a second support arm. The firstsupport arm and the second support arm connectable with respect to anunderside of a vehicle so as to be pivotable about a first axis orientedgenerally parallel to the ground and a second axis oriented generallyparallel to the ground, respectively. The step assist further comprisesa step member having an upper stepping surface. The first support armand the second support arm are connected to the step member so that thefirst support arm and the second support arm are pivotable with respectto the step member about a third axis and a fourth axis, respectively.The fourth axis is located inboard from the third axis. The firstsupport arm and the second support arm allow the step member to movebetween a retracted position and a deployed position downward andoutboard from the retracted position. As the step assist is viewed in aplane perpendicular to said first axis, the first axis and the thirdaxis define a first line and the second axis and the fourth axis definea second line. The first line and the second line intersect at aninstantaneous center of rotation of the step member. When the stepmember is in the retracted position, the instantaneous center ofrotation is located at or inboard of the upper stepping surface.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first support arm and a second support arm. The firstsupport arm and the second support arm are connectable with respect toan underside of a vehicle so as to be pivotable about a first axisoriented generally parallel to the ground and a second axis orientedgenerally parallel to the ground, respectively. The step assist furthercomprises a step member having an upper stepping surface. The firstsupport arm and the second support arm are connected to the step memberso that the first support arm and the second support arm are pivotablewith respect to the step member about a third axis and a fourth axis,respectively. The fourth axis is located inboard from the third axis.The first support arm and the second support arm allow the step memberto move between a retracted position and a deployed position downwardand outboard from the retracted position. At least a portion of theupper stepping surface initially moves upward as the step member movesfrom the retracted position to the deployed position.

In accordance with another embodiment, a retractable vehicle step assistcomprises a first support arm and a second support arm. The firstsupport arm and the second support arm are connectable with respect toan underside of a vehicle so as to be pivotable about a first axisoriented generally parallel to the ground and a second axis orientedgenerally parallel to the ground, respectively. The step assist furthercomprises a step member having an upper stepping surface. The firstsupport arm and the second support arm are connected to the step memberso that the first support arm and the second support arm are pivotablewith respect to the step member about a third axis and a fourth axis,respectively. The fourth axis is located inboard from the third axis.The first support arm and the second support arm allow the step memberto move between a retracted position and a deployed position downwardand outboard from the retracted position. The upper stepping surfacefollows a deployment path as said step member moves from said retractedposition to said deployed position. The deployment path includes aninitial upward component.

All of these and other embodiments are intended to be within the scopeof the invention herein disclosed. This and other embodiments of thepresent invention will become readily apparent to those skilled in theart from the following detailed description of the preferred embodimentshaving reference to the attached figures, the invention not beinglimited to any particular preferred embodiment or embodiments disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

Having thus summarized the general nature of the invention and itsessential features and advantages, certain preferred embodiments andmodifications thereof will become apparent to those skilled in the artfrom the detailed description herein having reference to the figuresthat follow, of which:

FIG. 1 is a side elevation view of a retractable vehicle step inaccordance with one preferred embodiment of the invention;

FIG. 2 is a front elevation view of the retractable vehicle step of FIG.1.

FIG. 3 is a side elevation view of a retractable vehicle step inaccordance with another preferred embodiment of the invention, in thedeployed position;

FIG. 4 is an exploded perspective view of the retractable vehicle stepof FIG. 3;

FIG. 5 is a side elevation view of the retractable vehicle step of FIG.3, in the retracted position;

FIGS. 6A–6B are perspective views of the retractable vehicle step asused in connection with a vehicle;

FIG. 7 is a side view of a further embodiment of a retractable vehiclestep, in the extended or deployed position;

FIG. 8 is a side view of the embodiment of FIG. 7, in the retractedposition;

FIG. 9 is a perspective view of the embodiment of FIG. 7;

FIG. 10 is a perspective view of a clutch assembly for use in connectionwith the retractable vehicle step;

FIG. 11 is an exploded perspective view of the clutch assembly of FIG.10;

FIG. 12 is a perspective view of a further embodiment of the retractablevehicle step, in the deployed position; and

FIG. 13 is a perspective view of the embodiment of FIG. 12, in theretracted position.

FIG. 14 is a side view of a further embodiment of a retractable vehiclestep, in the retracted position.

FIG. 15 is a side view of the embodiment of FIG. 14, in the deployedposition.

FIG. 16 is a side view of a further embodiment of a retractable vehiclestep, in the retracted position.

FIG. 17 is a side view of the embodiment of FIG. 16, in the deployedposition.

FIG. 18 is a side view of a further embodiment of a retractable vehiclestep, in the retracted position.

FIG. 19 is a side view of the embodiment of FIG. 18, in the deployedposition.

FIG. 20 is a side view of a further embodiment of a retractable vehiclestep, in the retracted position.

FIG. 21 is a side view of the embodiment of FIG. 20, in the deployedposition.

FIG. 22 is a side sectional view of a further embodiment of aretractable vehicle step, in the retracted position.

FIG. 22A is a further side sectional view of the embodiment of FIG. 22.

FIG. 23 is a side sectional view of the embodiment of FIG. 22, in thedeployed position.

FIG. 24 is a perspective view of the retractable step of FIG. 22, whenin use on a vehicle and in the retracted position.

FIG. 25 is a perspective view of the retractable step of FIG. 22, whenin use on a vehicle and in the deployed position.

FIG. 26 is a schematic depiction of a retractable step system suitablefor implementing various embodiments of the retractable step.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As a preliminary matter, it should be noted that the terms “forward,”“front” and “outboard” are used interchangeably herein, as are the terms“rearward,” “rear” and “inboard,” when describing components of the stepstructures disclosed herein. These terms are to be understood withreference to a direction of ingress into a vehicle,“forward”/“front”/“outboard” meaning generally toward the exterior ofthe vehicle, and “rearward”/“rear”/“inboard” meaning generally towardthe interior of the vehicle.

FIGS. 1 and 2 depict the lower portion of a vehicle 10 having anunderbody 12, an exterior 14, a vertical underbody portion 16 and anunder panel 18. A retractable vehicle step 20 is shown associated withthe vehicle 10. Referring specifically to FIG. 2, the retractablevehicle step 20 has a stepping member 22, which consists of a steppingdeck 24 with an outboard end 24 a, an inboard end 24 b, integrallyformed support brackets 26 a, 26 b, and drive brackets 28 a, 28 blocated inward of the support brackets 26 a, 26 b. The support brackets26 a, 26 b are pivotally connected to support arms 30 a, 30 b via clevispins 32 a, 32 b, at an end of the support brackets 26 a, 26 b oppositethe stepping deck 24. Similarly, the support arms 30 a, 30 b arepivotally connected to anchor brackets 34 a, 34 b via clevis pins 36 a,36 b, at an end of each support arm opposite the support brackets 26 a,26 b. The anchor brackets 34 a, 34 b are rigidly connected to theunderbody 12 by welding, bolting, riveting or other techniques known tothose skilled in the art.

The drive brackets 28 a, 28 b of the stepping member 22 are pivotallyconnected to a drive arm 38 via clevis pins 40 a, 40 b, at an end of thedrive brackets 28 a, 28 b opposite the stepping deck 24. As best seen inFIG. 2, the drive arm 38 preferably has an H configuration and ispivotally connected to anchor brackets 42 a, 42 b via clevis pins 44 a,44 b at an end of the drive arm 38 opposite the drive brackets 28 a, 28b. The anchor brackets 42 a, 42 b are rigidly connected to the underbody12 by welding, bolting, riveting or other techniques known to thoseskilled in the art.

Accordingly, the retractable vehicle step 20 defines the following axesof rotation, best seen in FIG. 2: a first axis A—A about which thesupport arms 30 a, 30 b rotate with respect to the underbody 12 and/oranchor brackets 34 a, 34 b; a second axis B—B about which the drive arm38 rotates with respect to the underbody 12 and/or anchor brackets 42 a,42 b; a third axis C—C about which the support arms 30 a, 30 b andsupport brackets 26 a, 26 b rotate with respect to each other; and afourth axis D—D about which the drive arm 38 and the drive brackets 28a, 28 b rotate with respect to each other. FIG. 1, as a side elevationview of FIG. 2, depicts the axes A—A, B—B, C—C, D—D as points. The firstaxis A—A is spaced from the third axis C—C by a first distance X and thesecond axis B—B is spaced from the fourth axis D—D by a second distanceY. (In other words, the first axis A—A is spaced from the rotatableconnection of the support arms 30 a, 30 b to the step member 22 by thefirst distance X, and the second axis B—B is spaced from the rotatableconnection of the drive arm 38 to the step member 22 by the seconddistance Y.) In one embodiment, the first and second distances X, Y areunequal; in another embodiment the first distance X is greater than thesecond distance Y. In one embodiment, the first axis A—A is locatedupward from the second axis B—B.

The first axis of rotation A—A is oriented generally parallel to theground and/or a lower edge 19 of the vertical underbody portion 16, andthe second axis of rotation B—B is also oriented generally parallel tothe ground and/or the lower edge 19. (It should be understood that, asused herein, “parallel to the ground” means generally parallel to ariding plane of the vehicle upon which the retractable step is mounted,which riding plane intercepts the contact patch of the two wheels on theside of the vehicle on which the retractable step in question ismounted.) The third and fourth axes C—C, D—D are oriented generallyparallel to the first and second axes A—A, B—B.

With further reference to FIG. 1, the first axis A—A is spaced from thesecond axis B—B by a third distance M and the third axis C—C is spacedfrom the fourth axis D—D by a fourth distance N. In one embodiment, thethird and fourth distances M, N are unequal; in another embodiment thethird distance M is greater than the second distance N. In oneembodiment, a line connecting the first axis A—A and the third axis C—Cis non-parallel to a line connecting the second axis B—B and the fourthaxis D—D when the retractable vehicle step 20 is in the retracted and/ordeployed position. In one embodiment, the line connecting the first axisA—A and the third axis C—C is angularly displaced from vertical by asmaller angle than is the line connecting the second axis B—B and thefourth axis D—D, when the retractable vehicle step 20 is in the deployedposition.

In one embodiment, as seen in FIG. 1, a first aspect ratio may bedefined as the ratio between (1) the distance between the first andsecond axes A—A, B—B and (2) the length of the arms 30 a, 30 b asdefined by the distance between the first and third axes A—A, C—C. Inthe embodiment shown in FIG. 1, the first aspect ratio is about 0.76.Likewise, a second aspect ratio may be defined as the ratio between (1)the distance between the first and second axes A—A, B—B and (2) thelength of the drive arm 38 as defined by the distance between the secondand fourth axes B—B, D—D. In the embodiment shown in FIG. 1, the secondaspect ratio is about 0.91. A third aspect ratio may be defined as theratio between (1) the distance between the first and second axes A—A,B—B and (2) the distance between the third and fourth axes C—C, D—D. Inthe embodiment shown in FIG. 1, the third aspect ratio is about 1.32.

With reference now to FIG. 1, a motor 46 is rigidly mounted to theunderbody 12 on a mounting bracket (not shown) adjacent the retractablevehicle step 20. The motor 46 turns a pinion gear 48 about an axisroughly parallel to the plane defined by the underbody 12. The piniongear 48 meshes with drive teeth 50 formed at the end of the drive arm38. Actuation of the motor 46 causes the pinion gear 48 to rotate andthe drive arm 38 to counter-rotate with respect to the motor 46 andpinion gear 48, about the clevis pin 44 a. As the drive arm 38 rotatesit pushes the stepping member 22 by virtue of its connection to thedrive brackets 28 a, 28 b. Thus, when the motor 46 is caused to rotate,the motor 46 moves the retractable vehicle step 20 between a retractedposition A wherein the stepping deck is desirably generally positionedinward from the exterior of the vehicle or fixed running board and anextended position B in which the stepping deck is extended sufficientlyto provide a step for at least the forefoot portion of a user's foot. Asthe retractable vehicle step 20 moves between the retracted position Aand the extended position B under the power of the motor 46, the supportarms 30 a, 30 b rotate with respect to the clevis pins 36 a, 36 b and 32a, 32 b and support and guide the motion of the retractable vehicle step20. The extended position B is reached when the support arms 30 a, 30 bcontact a stop 52 which is preferably mounted on the vertical underbodyportion 16. In one embodiment (best seen in FIG. 1), the stepping deck24 is tilted upward when in the retracted position A, with the outboardend 24 a located upward from the inboard end 24 b.

When the retractable vehicle step 20 is in the extended position B, adownward force exerted on the stepping deck 24 causes the support arms30 a, 30 b to bear against the stop 52. This arrangement causes the loadon the stepping deck 24 to be borne primarily by the support brackets 26a, 26 b, support arms 30 a, 30 b and the stop 52. In the extendedposition B, the retractable vehicle step 20 takes on a geometry suchthat the support brackets 26 a, 26 b, and support arms 30 a, 30 b areloaded in tension. The clevis pins 32 a, 32 b define a pivot axis of thestepping member 22. The torque generated by a load on the stepping deck24 is opposed by the drive arm 38, which is thus loaded in axialcompression between the clevis pins 40 a, 40 b and 44 a, 44 b. Becausethe clevis pins 44 a, 44 b are fixed in the anchor brackets 42 a, 42 b,the motor 46 is isolated from the load on the stepping deck 24.

This aspect of the retractable vehicle step 20 prevents damage to themotor by eliminating “back-loading,” as there is no torque reactionabout the end of the drive arm 38, even when very heavy loads are placedon the stepping deck 24. Thus the motor 46 is not needed to exert acounter-torque on the drive arm 38 to support the load on the steppingdeck 24. This feature also eliminates the need for balky, unreliableclutches or any other means of disconnecting the motor 46 from theretractable vehicle step 20, or retractable stops or the like to engageand support the vehicle step 20 when in the extended position.

The retractable vehicle step 20 functions in this manner when in theextended position B so long as the drive arm 38 is rotated further awayfrom the vertical in a counterclockwise direction (as shown in FIG. 1)than are the support arms 30 a, 30 b. That is, when the drive arm 38 isparallel to, or displaced clockwise beyond parallel to, the support arms30 a, 30 b, the drive arm 38 will not maintain the support arms 30 a, 30b against the stop 52. Rather, the retractable vehicle step 20 will tendto move toward the retracted position A, and the drive arm 38 will tendto rotate counterclockwise (in FIG. 1) about the clevis pins 44 a, 44 b.In this situation the motor 46 would be needed to exert a counter-torqueon the drive arm 38, to maintain the retractable vehicle step 20 in theextended position B. As mentioned above, it is undesirable to requirethe motor 46 to function in this manner.

Advantageously, some or all of the arms 30 a, 30 b, 38 are connected tothe step member 22 within a connection region 31 which is locatedrearward and upward from the stepping deck 24. This configurationminimizes the length and the downward and forward travel of the arms 30a, 30 b, 38 while facilitating a long overall “reach” for the step 20,with convenient placement of the stepping deck 24 when the step is inthe extended position. Furthermore, this arrangement permits the use,where desired, of an angled step member 22 (see FIG. 1) which can beretracted against the underbody 12 with minimal loss of groundclearance.

In one embodiment, when the step 20 is viewed from the side, in a planeperpendicular to the first axis (see FIG. 1) the third and fourth axescomprise points in the connection region 31, and a line extendingthrough the points forms an included angle α of about 10 degrees withrespect to the upper surface of the stepping deck 24. In anotherembodiment, the angle α may be between about 5 and 20 degrees. In stillother embodiments, the fourth axis may be located anywhere within theconnection region 31 rearward and upward of the third axis and the angleα may thus be any angle greater than 0 degrees and less than 90 degrees.

A dust cover or cap 54 may be mounted to the lower body panel 18 toprovide a storage location for the stepping member 22 and prevent dustor grime from collecting on the stepping deck 24.

With these features the retractable vehicle step 20 provides a practicalstepping assist for a vehicle user, which can be quickly moved into anextended position for use and retracted out of the way when necessary.As detailed above, this functionality is provided with a minimum ofmechanical complexity and a high level of reliability. Moreover, theretractable vehicle step 20 is easily connected to a vehicle's existingsystems to allow even greater usability. For example, the motor 46 maybe connected to the vehicle's electrical system to cause the vehiclestep 20 to quickly move to the extended position upon shutting off thevehicle's engine, placing the vehicle in park, opening a door, orsignaling the power door-lock system with a remote device or controlsuch as a key fob control. Similarly, the motor 46 may be signaled toretract the vehicle step upon starting the engine, placing the vehiclein drive, closing or locking the door(s) with which the step isassociated, etc.

Another embodiment of a retractable vehicle step 120 is shown in FIGS.3–5. The retractable step 120 comprises a stepping member 122 thatincludes a support section or stepping deck 124 bolted or otherwiserigidly connected to an extension section or a support bracket 126. Thestepping deck 124 has an outboard end 124 a and an inboard end 124 b,and defines an upper stepping surface 124 c. Front and rear support arms130 a, 130 b are rotatably connected to the support bracket 126 via pins132 a, 132 b. A rigid frame 134, which may be configured as necessaryfor connection to the vehicle underbody 12, provides a secure mountingfor the support arms 130 a, 130 b which are rotatably mounted to theframe 134 via pins 136 a, 136 b. It will be appreciated, however, thatany suitable structure or technique (other than the frame 134) may beemployed to rotatably connect the arms 130 a, 130 b to the vehicle.

As with the embodiment shown in FIGS. 1–2, the retractable vehicle step120 depicted in FIGS. 3–5 defines the following axes of rotation, bestseen in FIG. 4: a first axis A—A about which the front support arm 130 arotates with respect to the underbody 12 and/or frame 134; a second axisB—B about which the rear support arm 130 b rotates with respect to theunderbody 12 and/or frame 134; a third axis C—C about which the frontsupport arm 130 a and support bracket 126 rotate with respect to eachother; and a fourth axis D—D about which the rear support arm 130 b andsupport bracket 126 rotate with respect to each other. FIG. 3, as a sideelevation view of FIG. 4, depicts the axes A—A, B—B, C—C, D—D as points.The first axis A—A is spaced from the third axis C—C by a first distanceX and the second axis B—B is spaced from the fourth axis D—D by a seconddistance Y. (In other words, the first axis A—A is spaced from therotatable connection of the front support arm 130 a to the step member122 by the first distance X, and the second axis B—B is spaced from therotatable connection of the rear support arm 130 b to the step member 22by the second distance Y.) In one embodiment, the first and seconddistances X, Y are unequal; in another embodiment the first distance Xis greater than the second distance Y. In one embodiment, the first axisA—A is located upward from the second axis B—B.

The first axis of rotation A—A is oriented generally parallel to theground and/or the lower edge 19 (see FIG. 5), and the second axis ofrotation B—B is also oriented generally parallel to the ground and/orthe lower edge 19. The third and fourth axes C—C, D—D are orientedgenerally parallel to the first and second axes A—A, B—B.

With further reference to FIG. 3, the first axis A—A is spaced from thesecond axis B—B by a third distance M and the third axis C—C is spacedfrom the fourth axis D—D by a fourth distance N. In one embodiment, thethird and fourth distances M, N are unequal; in another embodiment thethird distance M is greater than the second distance N. In oneembodiment, a line connecting the first axis A—A and the third axis C—Cis non-parallel to a line connecting the second axis B—B and the fourthaxis D—D when the retractable vehicle step 120 is in the retractedand/or deployed position. In one embodiment, the line connecting thefirst axis A—A and the third axis C—C is angularly displaced fromvertical by a smaller angle than is the line connecting the second axisB—B and the fourth axis D—D, when the retractable vehicle step 120 is inthe deployed position.

In one embodiment, as seen in FIG. 3, a first aspect ratio may bedefined as the ratio between (1) the distance between the first andsecond axes A—A, B—B and (2) the length of the front arm 130 a asdefined by the distance between the first and third axes A—A, C—C. Inthe embodiment shown in FIG. 3, the first aspect ratio is about 0.75.Likewise, a second aspect ratio may be defined as the ratio between (1)the distance between the first and second axes A—A, B—B and (2) thelength of the rear arm 130 b as defined by the distance between thesecond and fourth axes B—B, D—D. In the embodiment shown in FIG. 3, thesecond aspect ratio is about 0.93. A third aspect ratio may be definedas the ratio between (1) the distance between the first and second axesA—A, B—B and (2) the distance between the third and fourth axes C—C,D—D. In the embodiment shown in FIG. 3, the third aspect ratio is about1.35.

With reference to FIG. 4, each of the support arms 130 comprises agenerally planar, unitary member which forms two coaxial bearing members131 at either end thereof. The coaxial bearing members may comprisecoaxial bores which engage pins in the frame and step member torotatably connect the support arm to each. In other embodiments thecoaxial bearing members may comprise coaxial axle portions which engagebores formed in the frame/step member to provide the rotatableconnections. Alternatively, one or both of the support arms may form asingle bearing member at one or both ends, comprising a singlefull-width bore or a single, central partial-width bore.

The spacing of the coaxial bearing members 131 defines a connectionwidth CW at each end of each support arm. The connection widthrepresents the distance between the opposite ends of the engagement ofthe bearing members with the frame/stepping member. For example, in FIG.4 the support arm 130 a is rotatably connected to the frame along anupper connection width, which equals the distance between the outeredges of the coaxial bearing members 131. The support arm 130 a isconnected to the step member along a lower connection width. The supportarm 130 b likewise defines an upper connection width and a lowerconnection width. These four connection widths are shown in FIG. 4 asbeing approximately equal, but they may be varied in relative size asdesired.

The support arms 130 a, 130 b also include a rigid crosspiece 133interconnecting the bearing members 131. The crosspiece isadvantageously of sufficient strength to prevent the support arms 130 a,130 b from substantially deflecting from their planar configuration whena user steps on the stepping deck 124. The crosspiece may take on anysuitable configuration, such as the full-size member shown, or a seriesof individual cross members extending horizontally or diagonally in an“X” pattern, etc. The high rigidity of the crosspiece and the arms 130a, 130 b as a whole advantageously permits the width of the arms to beminimized while nonetheless providing stable support for the steppingdeck 124 when in the extended position.

The front and rear support arms may take on other forms andconfigurations, but desirably each comprises a generally planar linkageconnecting the step member to the frame. A “generally planar linkage”may advantageously comprise a generally planar, unitary member such assupport arm 130 a or support arm 130 b as shown in FIG. 4. Analternative “generally planar linkage” comprises two or more separatearms (employed in place of a single unitary arm) interconnecting theframe and step member, the arms being coplanar by virtue of a commonupper axis of rotation associated with rotatable connection of the armsto the frame, and a common lower axis of rotation associated withrotatable connection of the arms to the step member opposite the frame.As with a unitary arm, a multiple-arm planar linkage defines at eitherend thereof a connection width extending between the outer edges of thecoaxial bearing members formed by the outermost arms making up thelinkage.

With further reference to FIGS. 3 and 4, the support bracket 126 maycomprise any suitable structural member having sufficient rigidity toresist bending about its horizontal and longitudinal axes. Thus the boxconfiguration shown in FIG. 4 is particularly suitable, but thoseskilled in the art will appreciate that the bracket 126 can take onother shapes known to those skilled in the art. The relatively smallconnection width of the arms 130 permits the bracket 126 to be made ofminimal width as well. By making the bracket 126 of sufficient length,the stepping deck 124 will be positioned properly for easy use when thestep 120 is in the deployed position (see FIG. 3) and the length of thearms 130 can be kept to a minimum.

As best seen in FIG. 3, the support bracket 126 preferably forms anangle with the stepping deck 124, and thus extends upward and rearwardfrom the substantially level (when in the extended position) uppersurface of the deck 124. Consequently, the preferred angledconfiguration further enables the length of the support arms 130 to beminimized. The step member 122 may thus be said to move between anupward-rotated orientation in the retracted position (FIG. 5) to adownward-rotated orientation in the deployed position (FIG. 3). In otherwords, the step member 122 rotates downward about its connection withthe support arm 130 b when moving to the deployed position, and rotatesupward about the same connection when moving to the retracted position.When in the retracted position the stepping deck 124 tilts upward (withthe outboard end 124 a located upward from the inboard end 124 b),minimizing the total downward protrusion of the retractable step fromthe vehicle underbody. Desirably, this upward tilt is at least 10° and,preferably at least 20°, to facilitate any water or debris draining offthe step and thereby enhance its safety when in use.

With the stepping member 122 moveably connected to the frame 134 via thesupport arms 130 a, 130 b, it can be moved between the retractedposition A and the extended position B, as shown in FIGS. 5 and 3,respectively. As with the embodiment described previously, theretractable step 120 provides a sturdy step for a vehicle user when inthe extended position B. The geometry of the stepping member 122,support arms 130, and frame 134 causes the arm 130 a to be loaded intension and the arm 130 b to be loaded in compression when a load isapplied to the stepping deck 124 in a manner similar to that shown inFIG. 1. Accordingly, the arm 130 b urges the arm 130 a against a stop152 when a user steps on the stepping deck 124, by applying a horizontalreaction force to the step member 122. The stop 152 prevents motion ofthe drive arm 138 beyond a location chosen so that when the drive arm138 strikes the stop 152, the step 120 is in a configuration where ittends to move further away from the retracted position upon applicationof a load to the stepping deck 124, but is prevented from doing so byvirtue of the stop. Due to this convergence of factors, the extendedstep 120 firmly maintains its deployed position without input from motor146 (discussed in further detail below), when stepped upon by a user.This feature eliminates the need for a separate locking mechanism, oftenseen in the form of a hydraulic lock, to maintain the stepping deck inthe deployed position when in use. Consequently, this feature enhancesthe ease of use of the retractable step, as the user is not required tooperate or disengage the lock when retracting or deploying the step,thereby eliminating an undesirable aspect of prior-art retractable stepsystems.

A drive system 137 provides powered movement of the step 120 between theretracted and the extended position. The drive system 137 comprises adrive arm 138 coupled to a rotor 139, both of which are rotatablymounted on the pin 136 a, and a motor 146 drivingly connected to thedrive arm 138 via the rotor 139. The drive arm 138 is connected to therotor 139 so as to rotate in concert therewith about the pin 136 a. Inanother embodiment, the rotor and drive arm form an integral unit.

The motor 146 can be mounted to the frame 134, to the vehicle underbody,or in any other suitable location. The motor 146 drives the rotor, drivearm, stepping member, etc. via, for example, a worm gear 147 that mesheswith teeth (not shown) formed on the circumference of the rotor 139. Inanother embodiment, the motor may comprise a linear actuator that pushesor pulls on the circumference of the rotor 139 in order to rotate it ineither direction. Of course, any suitable means of coupling the motor tothe rotor/drive arm may be used. Advantageously, a window motor may beused to drive the apparatus. Preferably, the motor will adjust forchanges in temperature.

The drive system 137, or any drive system employed with any of theembodiments of the retractable step disclosed herein, may advantageouslyinclude a system to stop the motion of the step member, arms, etc. whenan obstruction is encountered within the range of motion of the step, orwithin the moving parts of the step. Such a system reduces the risk of apinching injury when a person has inadvertently inserted his or herhand, arm, etc. within the mechanism, and also reduces the potential fordamaging the step member or other parts of the retractable step when itapproaches or strikes a hard object such as a curb. It is contemplatedthat a standard anti-pinch/anti-strike system may be used, as is knownin the art.

Advantageously, one or both of the arms 130 a, 130 b are connected tothe step member 122 within a connection region 131 (see FIG. 3) which islocated rearward and upward from the stepping deck 124. Thisconfiguration minimizes the length and the downward and forward travelof the arms 130 a, 130 b while facilitating a long overall “reach” forthe step 120, with convenient placement of the stepping deck 124 whenthe step is in the extended position. Furthermore, this arrangementpermits the use, where desired, of an angled step member 122 which canbe retracted against the underbody 12 with minimal loss of groundclearance.

In one embodiment, when the step 120 is viewed from the side, in a planeperpendicular to the first axis (see FIG. 3) the third and fourth axescomprise points in the connection region 131, and a line extendingthrough the points forms an included angle β of about 10 degrees withrespect to the upper surface of the stepping deck 124. In anotherembodiment, the angle β may be between 5 and 20 degrees. In still otherembodiments, the fourth axis may be located anywhere within theconnection region 131 rearward and upward of the third axis and theangle β may thus be any angle greater than 0 degrees and less than 90degrees.

A dust cover or cap 154 may be mounted to the lower body panel 18 toprovide a storage location for the stepping member 122 and prevent dustor grime from collecting on the stepping deck 124. The dust cover 154advantageously has a portion that protrudes downward from the lowersurface of the vehicle and extends across the gap formed between theupper surface of the deck 124 and the adjacent vehicle structure, andmay extend or curl around the outer edge of the deck 124. Thus the dustcover 154 forms a protective pocket around the outer edge and uppersurface of the deck 124. It has been found that the dust cover 154reduces the accumulation of water, dust, mud and/or debris on the deck,providing a substantial benefit in terms of safety and aesthetics whilereducing the chance of soiling the user's clothes when he or she stepson or stands near the deck.

The retractable step thus utilizes a relatively compact linkage systemto support the stepping deck 124 when in the deployed position. Therelatively short, compact support arms 130 can be made of minimal width,as can the frame 134 and support bracket 126. The stepping deck 124 canthus be made substantially wider than the frame/support arms/supportbracket. In other words the stepping deck 124 is preferablysubstantially wider than any of the connection width(s) defined by thesupport arms. Advantageously, the stepping deck is about 2–8 times aswide as the frame, support arms, support bracket or any of theconnection width(s) defined by the support arms. Thus the retractablestep provides a wide stepping deck for the vehicle user while minimizingthe width and space requirements of the frame, linkage system, etc.

The wide stepping deck 124 and relatively narrow frame/supportarms/support bracket permit a single retractable step to serve as aconvenient step assist for two adjacent doors of a vehicle, withoutoccupying a large amount of space under the vehicle with the frame,support arms and support bracket. FIG. 6A shows a vehicle 200 having onone side thereof a front door 202 and an adjacent rear door 204. In FIG.6A no portion of the retractable vehicle step is visible because it isin the retracted position. FIG. 6B shows the stepping deck 124 of theretractable step after it has moved to the extended position (uponopening the front door 202 or in response to other actions as detailedabove). It is readily seen that the deck 124 provides a convenient stepassist for a person desiring to enter the vehicle through either of thedoors 202, 204. Where the deck 124 extends in front of about ¼ of thewidth of each door, the deck will be sufficiently wider than the user'sfoot to provide an easy-to-use step. Extending the deck to cover about ½the width of each door provides an additional safety factor above a¼-width deck. A deck which extends across substantially the entire widthof both doors is most advantageous in that it essentially eliminates theneed for the user to look down to the step when placing a foot upon it,facilitating easy use by a person carrying a large number of items withthem.

More broadly stated, the novel configuration of the retractable steppermits the width of the stepping deck to be selected largelyindependently of the width of the frame, arms and/or support bracket.Consequently, a stepping deck that is intended to serve as a step fortwo adjacent doors need not extend the entire width of the doors. It mayinstead be only about 4–5 feet wide (in comparison to a standard fixedrunning board which is typically 6–8 feet in width), providing aconvenient step while keeping the size and weight of the overall deviceto a minimum. It has been found that this particular width provides anoptimal balance between providing ease of use (via a relatively widedeck) and avoiding an overly large, bulky device. Likewise, the steppingdeck of a retractable step intended for use with a single vehicle doormay be reduced to an optimal deck width which is less than the entirewidth of the door.

FIGS. 7–11 depict another embodiment 220 of the retractable vehiclestep, attached to a vehicle underbody 12 having a doorjamb 50 adapted toreceive a vehicle door (not shown), an under panel 18, and asubstantially vertical outer panel or surface 52. The retractable step220 comprises a stepping member 222 that includes a stepping deck 224bolted or otherwise rigidly connected to a support bracket 226. Frontand rear support arms 230 a, 230 b are rotatably connected to thesupport bracket 226 via pins 232 a, 232 b. The rear support arm includesa retraction stop 231 a and a deployment stop 231 b. A rigid frame 234,which may be configured as necessary for connection to the vehicleunderbody 12, provides a secure mounting for the support arms 230 a, 230b which are rotatably mounted to the frame 234 via pins 236 a, 236 b.The frame 234 may include a forward extension 235 which forms a rail 235a for attachment of the frame 234 to the vehicle underbody 12, viabolting, riveting, welding or other conventional methods. It will beappreciated, however, that a wide variety of structure may be used inplace of or in addition to the extension 235 and rail 235 a tofacilitate attachment of the frame 234 to different vehicle makes andmodels. Likewise, it will be appreciated that any suitable structure ortechnique (other than the frame 234) may be employed to rotatablyconnect the arms 230 a, 230 b to the vehicle.

The front support arm 230 a is rotatable about a first axis of rotationA—A which is oriented generally parallel to the lowest edge or extension300 of the vehicle underbody 12, and the rear support arm 230 b isrotatable about a second axis of rotation (not shown) which is alsooriented generally parallel to the lowest edge 300. The front arm 230 aand the support bracket 226 are rotatable with respect to each otherabout a third axis of rotation C—C, and the rear arm 230 b and thebracket 226 are rotatable with respect to each other about a fourth axisof rotation D—D. The third and fourth axes C—C, D—D are orientedgenerally parallel to the first and second axes.

For the sake of clarity, the distances between the various axes A—Athrough D—D are not marked on FIGS. 7 and 8; however, the followingdiscussion of the geometry of the layout of the axes applies with equalforce to the embodiment of FIGS. 7–9, as it did with regard to theembodiments discussed above. With reference to FIG. 7, the first axisA—A is spaced from the third axis C—C by a first distance and the secondaxis B—B is spaced from the fourth axis D—D by a second distance. In oneembodiment, the first and second distances are unequal; in anotherembodiment the first distance is greater than the second distance. Inone embodiment, the first axis A—A is located upward from the secondaxis B—B.

The first axis A—A is spaced from the second axis B—B by a thirddistance and the third axis C—C is spaced from the fourth axis D—D by afourth distance. In one embodiment, the third and fourth distances areunequal; in another embodiment the third distance is greater than thesecond distance. In one embodiment, a line connecting the first axis A—Aand the third axis C—C is non-parallel to a line connecting the secondaxis B—B and the fourth axis D—D when the retractable vehicle step 220is in the retracted and/or deployed position. In one embodiment, theline connecting the first axis A—A and the third axis C—C is angularlydisplaced from vertical by a smaller angle than is the line connectingthe second axis B—B and the fourth axis D—D, when the retractablevehicle step 220 is in the deployed position.

In one embodiment, as seen in FIG. 7, a first aspect ratio may bedefined as the ratio between (1) the distance between the first andsecond axes and (2) the length of the front arm 230 a as defined by thedistance between the first and third axes A—A, C—C. In the embodimentshown in FIG. 7, the first aspect ratio is about 0.21. Likewise, asecond aspect ratio may be defined as the ratio between (1) the distancebetween the first and second axes and (2) the length of the rear arm 230b as defined by the distance between the second and fourth axes. In theembodiment shown in FIG. 7, the second aspect ratio is about 0.22. Athird aspect ratio may be defined as the ratio between (1) the distancebetween the first and second axes and (2) the distance between the thirdand fourth axes C—C, D—D. In the embodiment shown in FIG. 7, the thirdaspect ratio is about 1.00.

As depicted in FIGS. 7 and 8, the retractable step 220 is moveablebetween a retracted position A and an extended position B. When the step220 is in the extended position B, a downward force exerted on thestepping deck 24 causes the deployment stop 231 b to bear against thefront support arm 230 a. At this point the step 220 is in aconfiguration where it tends to move further away from the retractedposition B upon application of a load to the stepping deck 224, but isprevented from doing so by virtue of the deployment stop 231 b. Due tothis convergence of factors, the extended step 220 firmly maintains itsdeployed position without input from the motor 246 (discussed in furtherdetail below), when stepped upon by a user. This feature eliminates theneed for a separate locking mechanism, often seen in the form of ahydraulic lock, to maintain the stepping deck in the deployed positionwhen in use. Consequently, this feature enhances the ease of use of theretractable step, as the user is not required to operate or disengagethe lock when retracting or deploying the step, thereby eliminating anundesirable aspect of prior-art retractable step systems.

Advantageously, one or both of the arms 230 a, 230 b are connected tothe step member 222 within a connection region 231 (see FIG. 7) which islocated rearward and upward from the stepping deck 224. Thisconfiguration minimizes the length and the downward and forward travelof the arms 230 a, 230 b while facilitating a long overall “reach” forthe step 220, with convenient placement of the stepping deck 224 whenthe step is in the extended position. Furthermore, this arrangementpermits the use, where desired, of an angled step member 222 which canbe retracted against the underbody 12 and/or folded against the arms 230a, 230 b to compactly package the step 220 when retracted, which in turnfacilitates installation of the step 220 within a small space of theunderbody 12, and minimal loss of ground clearance.

The retractable step 220 shown in FIGS. 7–9 thus has a wide range ofmotion, such that the entirety of the stepping deck 224 is locatedoutboard of the first axis A—A when the step member is in the deployedposition B and at least a portion of the stepping deck 224 is locatedinboard of the second axis B—B when the step member is in the retractedposition A. In one embodiment, the upper surface of the stepping deck224 is the uppermost portion of the retractable step 220 outboard of thesupport bracket 226, when the step member 222 is in the deployedposition. In another embodiment, the upper surface of the stepping deck224 is located about 10–12 inches above the ground when the step member222 is in the deployed position. In another embodiment, the uppersurface of the stepping deck 224 is located about 10 inches above theground when the step member 222 is in the deployed position. In anotherembodiment, the upper surface of the stepping deck 224 is located about11 inches above the ground when the step member 222 is in the deployedposition. In another embodiment, the upper surface of the stepping deck224 is located about 12 inches above the ground when the step member 222is in the deployed position.

In one embodiment, when the step 220 is viewed from the side, in a planeperpendicular to the first axis (see FIG. 7) the third and fourth axescomprise points in the connection region 231, and a line extendingthrough the points forms an included angle γ of about 50 degrees withrespect to the upper surface of the stepping deck 224. In otherembodiments, the angle γ may be between 20 and 80 degrees, or between 40and 60 degrees. In still other embodiments, the fourth axis may belocated anywhere within the connection region 231 rearward and upward ofthe third axis and the angle γ may thus be any angle greater than 0degrees and less than 90 degrees.

In the embodiment shown in FIGS. 7 and 8, the upper surface of thestepping deck 224 may define a substantially horizontal plane in boththe extended and retracted positions.

FIGS. 7, 8 and 9 show that the front support arm 230 a preferably has abowed configuration, with a relatively straight midsection between twoangled end portions. This preferred geometry ensures that the retractionand deployment stops 231 a, 231 b will contact the front support arm 230a at a location which is spaced from its rotatable connections to thepins 232 a, 236 a. It has been found that shear loading of the arm 230 anear these connection points, such as that which may occur in thedeployed position absent the stop 231 b, can lead to failure in somecircumstances.

In the embodiment presently under discussion, when the retractable step220 is in the retracted position, it is concealed, preferably completelyconcealed, from the view of a typical standing adult curbside observerof the vehicle. In this position the stepping member 222, as well as theframe 234 and the remainder of the retractable step 220, is disposedbehind the lowest extension or lower edge 300 of the vehicle underbody12. Preferably, the forward edge of the stepping deck 224 is spaced atleast about 1.5–4.5 inches rearward of the lower portion of the outerpanel 52; more preferably, the forward edge is spaced at least about2.5–3.5 inches rearward of the lower portion of the panel 52; mostpreferably, the forward edge is spaced at least about 3.2 inchesrearward of the lower portion of the panel 52. Furthermore, thelowest-extending point 222 a of the stepping member 222 is situatedabove the lowest extension 300 of the underbody 12, or protrudes such anamount below the extension 300 (and/or is disposed sufficiently rearwardof the extension 300) that it substantially remains, and preferablycompletely remains, out of the field of view of a typical standing adultobserver positioned outside of the vehicle. In one embodiment, theretracted step 220 is not visible to an adult standing 5 feet from thevehicle; in another embodiment, the retracted step 220 is not visible toan adult standing 10 feet from the vehicle; in another embodiment, theretracted step 220 is not visible to an adult standing 20 feet from thevehicle.

This concealment is achieved primarily by providing a wide range ofmotion of the stepping member 222. The front and rear support arms 230a, 230 b are made sufficiently long, and/or provided with a sufficientlywide range of angular motion, to move the stepping member 222 rearwardand upward into the concealed, retracted position A. The arms 230 a, 230b are also made sufficiently long in comparison to the stepping member222, and are mounted to the frame 234 on pivot points spacedsufficiently rearward of the extension 300, to move the front edge ofthe stepping deck 234 behind the extension 300 during retraction. Theconnection points of the arms 230 a, 230 b to the frame 234 and steppingmember 222 are selected to prevent either arm from interfering with theother's motion over a wide range of travel. The frame 234 includesadequate clearance to accommodate the motion of the stepping member 222and arms 230 a, 230 b to and from the retracted position A. Thus, whenthe member 222 is retracted, substantially no portion of the step 200 isvisible to an ordinary “curbside” observer, and a vehicle with the step220 installed and retracted will appear substantially identical to suchan observer, to a “stock” version of the same vehicle.

FIG. 9 depicts a preferred drive system 237 for providing poweredmovement of the step 220 between the retracted and the extendedposition. The drive system 237 preferably comprises a drive arm 238which is drivingly coupled to the rear support arm 230 b, and is furthercoupled to a clutch assembly or torque limiter 239. The clutch assembly239 is in meshing engagement with a primary gear system 240 and a motor246. Alternatively, the motor 246 may drive the clutch assembly 239directly, and the primary gear system 240 may be omitted. A subframe 248may be provided for mounting the primary gear system 240 and/or motor246 with respect to the frame 234. The clutch assembly 239 and drive arm238 are preferably rotatably mounted to the frame 234 so that a drivingforce on the teeth of the clutch assembly 239 causes the assembly 239and the drive arm 238 to rotate together and move the step 220 to orfrom the retracted position.

FIGS. 10 and 11 show a preferred configuration of the clutch assembly239 and drive arm 238 in greater detail. The clutch assembly 239includes a broached or splined hub 250 which is configured for rotatableattachment to the frame 234. The drive arm 238 includes a broachedopening 252 to provide a positive connection to the hub 250 when mountedthereon. Adjacent the drive arm 238 is a first clutch member 254 formedfrom a high-friction clutch material as is known in the art, an inputgear 256 having conventional gear teeth for receiving a driving forceapplied by the primary gear system 240 and/or motor 246, and a secondclutch member 258, which is preferably similar to the first clutchmember 254. A broached washer 260 covers the clutch member 258, and abevel spring 262 and nut 264 (threadably engaged with the hub) securethe entire assembly to the hub 250. Thus, under pressure exerted by thespring and nut, the input gear 256 is frictionally coupled to the drivearm 238, hub 250 and washer 260 via the clutch members 254, 258.

In normal operation, the input gear 256 and the drive arm 238 willrotate together about their common axis of rotation, acting as if asingle component, to drive the step 220 between the retracted andextended positions under the power of the motor 246. However, underappropriate circumstances the clutch members 254, 258 will permitslippage to occur between the input gear 256 and the drive arm 238, suchthat relative angular motion occurs between the gear 256 and the arm238. One circumstance under which this may occur is when the motor 246is cut off from its power supply while the step is at or near theextended position, and the vehicle user must manually push the step intothe extended position. The clutch permits the step to be manuallyretracted in this manner without back-loading the motor 246, protectingthe motor from damage.

The clutch assembly 239 is also useful in a situation in which the step220 is being moved under power of the motor, but strikes an obstructionwhich prevents further motion of the step. In this situation, the clutchprevents damage to the motor (and possible injury where the step hasstruck a person's hand, leg, etc.) by allowing it to continue turningunder the power supplied to it while the step is immobilized, avoidingburn-out of the motor 246. This provides a further safety measure whichcan be used, if desired, in conjunction with a standardanti-pinch/anti-strike system as discussed above.

FIGS. 12 and 13 depict a further embodiment 420 of the retractablevehicle step, in which two or more retraction assemblies 450 areconnected to, and provide retraction and deployment of, a singlestepping deck 424. Each of the retraction assemblies 450 may comprisestructure which generally similar to any of the embodiments disclosedherein for the retractable vehicle step; however, the embodiment shownin FIGS. 12 and 13 utilizes the mechanism disclosed above in connectionwith FIGS. 3–5. One or both of the assemblies 450 may include a motorfor moving the step between the deployed position (FIG. 12) and theretracted position (FIG. 13).

The assemblies 450 are preferably coupled to the stepping deck 424 atlocations spaced inward from the outer edges of the deck 424. Thisconfiguration limits the maximum moment arm defined between a loadplaced on the deck 424 and either of the connection points to theassemblies 450, and reduces the lateral “footprint” occupied by the step420 when connecting the step to a vehicle.

FIGS. 14–15 depict another embodiment of the retractable vehicle step520, which may be similar to the embodiments discussed above (especiallythe embodiment depicted in FIGS. 7–9) except as disclosed below. Theretractable step 520, shown as attached to the vertical underbodyportion 16, comprises a stepping member 522 that includes a steppingdeck 524 bolted or otherwise rigidly connected to a support bracket 526.Front and rear support arms 530 a, 530 b are rotatably connected to thesupport bracket 526 via pins 532 a, 532 b. A rigid frame 534 andconnection bracket 541, each of which may be configured as necessary forconnection to the vertical underbody portion 16, provide a securemounting for the support arms 530 a, 530 b which are rotatably mountedto the frame 534 via pins 536 a, 536 b. The pin 536 b may also serve asa drive axle for the rear support arm 530 b, by virtue of furtherconnection to a suitable drive system (not shown). Accordingly, the pin536 b may have a larger diameter than the other pins 532 a, 532 b, 536a. In other embodiments, the pin 536 a may be employed as a drive axle,and a larger diameter may be selected for the pin 536.

The connection bracket 541 may be fixed to the vertical underbodyportion 16 (and the frame 534 fixed to the connection bracket 541) viabolting, riveting, welding or other conventional methods. It will beappreciated, however, that a wide variety of structure may be used inplace of or in addition to the connection bracket 541 to facilitateattachment of the frame 534 to different vehicle makes and models.Likewise, it will be appreciated that, while the frame shown ispreferred, any suitable structure or technique (other than the frame534) may be employed to rotatably connect the arms 530 a, 530 b to thevehicle.

As with the embodiments discussed above, the retractable vehicle step520 shown in FIGS. 14–15 defines a set of first through fourth axes A—Athrough D—D corresponding to the previously-discussed sets of axes. Forthe sake of clarity, the distances between the various axes A—A throughD—D are not marked on FIGS. 14–15; however, the following discussion ofthe geometry of the layout of the axes applies with equal force to theembodiment of FIGS. 14–15, as it did with regard to the embodimentsdiscussed above. With reference to FIG. 14, the first axis A—A is spacedfrom the third axis C—C by a first distance and the second axis B—B isspaced from the fourth axis D—D by a second distance. In one embodiment,the first and second distances are unequal; in another embodiment thefirst distance is greater than the second distance. In one embodiment,the first axis A—A is located upward from the second axis B—B.

The first axis A—A is spaced from the second axis B—B by a thirddistance and the third axis C—C is spaced from the fourth axis D—D by afourth distance. In one embodiment, the third and fourth distances areunequal; in another embodiment the third distance is greater than thesecond distance. In one embodiment, a line connecting the first axis A—Aand the third axis C—C is non-parallel to a line connecting the secondaxis B—B and the fourth axis D—D when the retractable vehicle step 520is in the retracted and/or deployed position. In one embodiment, theline connecting the first axis A—A and the third axis C—C is angularlydisplaced from vertical by a smaller angle than is the line connectingthe second axis B—B and the fourth axis D—D, when the retractablevehicle step 520 is in the deployed position.

The rearward surface of the front support arm 530 a tapers forward atupper and lower transitions 543 a, 543 b, thus forming a thinnerintermediate portion 545 between thicker end portions 549 a, 549 b. Thisarrangement permits the arms 530 a, 530 b to nest partly “within” eachother at the extremes of their range of motion, which in turn increasesthe range of motion of the step member 522 while permitting the ends ofthe arm(s) to be made thicker, to better withstand the forcesencountered at their rotatable connections to the frame and step member.With a greater range of motion thus imparted to the arms 530 a, 530 band step member 522, the member 522 can extend farther from the vehiclewhen deployed and retract further into the vehicle for improvedconcealment.

As seen in FIG. 14, the rear support arm 530 b has a thicker upperportion 551 which approaches or contacts the intermediate portion 545 ofthe front support arm 530 a, near the transition 543 a, when theretractable vehicle step 520 is in the retracted position A.Accordingly, the front support arm 530 a is shown rotated rearwardbeyond the point at which the arm 530 a would stop (by virtue of contactwith the rear support arm 530 b) if the arm 530 a had a uniformthickness. Generally, increased rearward range of motion can be realizedby causing the front arm 530 a to rotate to any point at which a portionof the rear arm 530 b is spaced from a line connecting the first andthird axes A—A, C—C, by an orthogonal distance less than half themaximum thickness of the front arm 530 a. The maximum increase in rangeof motion is achieved by causing the front arm 530 a to rotate to apoint at which the thinner intermediate portion 545 contacts the reararm 530 b.

FIG. 15 shows the nesting relationship of the arms 530 a, 530 b when theretractable vehicle step 520 is in the extended position B. A thinnerlower portion 553 of the rear support arm 530 b approaches or contactsthe intermediate portion 545 of the front support arm 530 a, near thetransition 543 b. Under the principles discussed above a wider forwardrange of motion is facilitated by the thinner intermediate portion 545,than would be possible were the front arm 530 a of a uniform thickness.

The retractable step 520 shown in FIGS. 14–15 thus has a wide range ofmotion, such that the entirety of the stepping deck 524 is locatedoutboard of the first axis A—A when the step member is in the deployedposition B and at least a portion of the stepping deck 524 is locatedinboard of the second axis B—B when the step member is in the retractedposition A.

FIGS. 16–17 depict another embodiment of the retractable vehicle step620, which may be similar to the embodiments discussed above except asdisclosed below. The retractable step 620, shown as attached to theunderbody 12, comprises a stepping member 622 that includes a steppingdeck 624 bolted or otherwise rigidly connected to a support bracket 626.Front and rear support arms 630 a, 630 b are rotatably connected to thesupport bracket 626 via pins 632 a, 632 b. A rigid frame 634 andconnection bracket 641, each of which may be configured as necessary forconnection to the underbody 12, provide a secure mounting for thesupport arms 630 a, 630 b which are rotatably mounted to the frame 634via pins 636 a, 636 b.

The frame 634 and connection bracket 641 may be fixed to the verticalunderbody portion 16 (and the frame 634 fixed to the connection bracket5641) via bolting, riveting, welding or other conventional methods. Itwill be appreciated, however, that a wide variety of structure may beused in place of or in addition to the connection bracket 641 tofacilitate attachment of the frame 634 to different vehicle makes andmodels. While the illustrated design is a preferred embodiment, it willbe appreciated that other suitable structures or techniques (aside fromthe frame 634) may be employed to rotatably connect the arms 630 a, 630b to the vehicle.

As with the embodiments discussed above, the retractable vehicle step620 shown in FIGS. 16–17 defines a set of first through fourth axes A—Athrough D—D corresponding to the previously-discussed sets of axes. Forthe sake of clarity, the distances between the various axes A—A throughD—D are not marked on FIGS. 16–17; however, the following discussion ofthe geometry of the layout of the axes applies with equal force to theembodiment of FIGS. 16–17, as it did with regard to the embodimentsdiscussed above. With reference to FIG. 16, the first axis A—A is spacedfrom the third axis C—C by a first distance and the second axis B—B isspaced from the fourth axis D—D by a second distance. In one embodiment,the first and second distances are unequal; in another embodiment thefirst distance is greater than the second distance. In one embodiment,the first axis A—A is located upward from the second axis B—B.

The first axis A—A is spaced from the second axis B—B by a thirddistance and the third axis C—C is spaced from the fourth axis D—D by afourth distance. In one embodiment, the third and fourth distances areunequal; in another embodiment the third distance is greater than thesecond distance. In one embodiment, a line connecting the first axis A—Aand the third axis C—C is non-parallel to a line connecting the secondaxis B—B and the fourth axis D—D when the retractable vehicle step 620is in the retracted and/or deployed position. In one embodiment, theline connecting the first axis A—A and the third axis C—C is angularlydisplaced from vertical by a smaller angle than is the line connectingthe second axis B—B and the fourth axis D—D, when the retractablevehicle step 620 is in the deployed position.

The rearward surface of the front support arm 630 a tapers forward toform a thinner intermediate portion 645 between thicker end portions 649a, 649 b. This arrangement permits the arms 630 a, 630 b to nest partly“within” each other when the retractable step 620 is in the deployedposition B, which in turn increases the forward range of motion of thestep member 622 while permitting the ends of the arm(s) to be madethicker, to better withstand the forces encountered at their rotatableconnections to the frame and step member. With a greater forward rangeof motion thus imparted to the arms 630 a, 630 b and step member 622,the member 622 can extend farther from the vehicle when deployed.

As seen in FIG. 17, the rounded lower portion of the rear support arm630 b approaches or contacts the thinner intermediate portion 645 of thefront support arm 630 a when the retractable vehicle step 620 is in thedeployed position B. Accordingly, the rear support arm 630 b is shownrotated forward beyond the point at which the arm 630 b would stop (byvirtue of contact with the front support arm 630 a) if the front arm 630a had a uniform thickness. Generally, increased forward range of motioncan be realized by causing the rear arm 630 b to rotate to any point atwhich a portion of the rear arm 630 b is spaced from a line connectingthe first and third axes A—A, C—C, by an orthogonal distance less thanhalf the maximum thickness of the front arm 630 a. The maximum increasein range of motion is achieved by causing the rear arm 630 b to rotateforward to a point at which the thinner intermediate portion 645contacts the rear arm 630 b.

The embodiment shown in FIGS. 16–17 is particularly suited for use inthe narrow space depicted, between a lower portion of a vehicle door 21which is located upward of an adjacent vehicle frame member 23. Withlittle room to retract rearward, the stepping deck 624 instead rotatesprimarily upward when retracting. Thus, in the depicted embodiment thefront edge 624 a of the stepping deck 624 is located above the firstaxis A—A when the step member 622 is in the retracted position A. Inaddition, the entirety of the stepping deck 624 may be situated forwardof the first axis A—A when the step member 622 is in the retractedposition A.

When retracted, the retractable vehicle step 620 is substantiallyconcealed from the view of an observer standing next to the vehicle,because the lower surface 624 d of the stepping deck 624 extends inwardand downward from the lower edge of the door 21 at an angle δ of about45–65 degrees with respect to vertical. The “upward” position of theretracted deck 624 also blocks the arms, frame, etc. from the view of atypical vehicle-side observer. The concealment may be further enhancedby painting or otherwise coloring the lower surface 624 d of thestepping deck with a dark color (black, dark gray, etc.) or coloring itto match the surrounding underbody, frame, etc.

FIGS. 18 and 19 depict another embodiment of the retractable vehiclestep 720, which may be similar to the embodiments discussed above exceptas disclosed below. The retractable step 720 comprises a stepping member722 that includes a stepping deck 724 bolted or otherwise rigidlyconnected to a support bracket 726. Front and rear support arms 730 a,730 b are rotatably connected to the support bracket 726 via pins 732 a,732 b. A rigid frame 734, which may be configured as necessary forconnection to the vertical underbody portion 16, provides a securemounting for the support arms 730 a, 730 b which are rotatably mountedto the frame 734 via pins 736 a, 736 b. The pin 736 b may also serve asa drive axle for the rear support arm 730 b, by virtue of furtherconnection to a suitable drive system (not shown). Accordingly, the pin736 b may have a larger diameter than the other pins 732 a, 732 b, 736a. In other embodiments, the pin 736 a may be employed as a drive axle,and a larger diameter may be selected for the pin 736 a.

The frame 734 may be fixed to the vertical underbody portion 16 viabolting, riveting, welding or other conventional methods. It will beappreciated, however, that a wide variety of structure may be used inplace of or in addition to the frame 734 to facilitate attachment of thearms 730 a, 730 b to the vehicle, or different vehicle makes and models.

As with the embodiments discussed above, the retractable vehicle step720 shown in FIGS. 18–19 defines a set of first through fourth axes A—Athrough D—D corresponding to the previously-discussed sets of axes. Forthe sake of clarity, the distances between the various axes A—A throughD—D are not marked on FIGS. 18–19; however, the following discussion ofthe geometry of the layout of the axes applies with equal force to theembodiment of FIGS. 18–19, as it did with regard to the embodimentsdiscussed above. With reference to FIG. 18, the first axis A—A is spacedfrom the third axis C—C by a first distance and the second axis B—B isspaced from the fourth axis D—D by a second distance. In one embodiment,the first and second distances are unequal; in another embodiment thefirst distance is greater than the second distance. In one embodiment,the first axis A—A is located upward from the second axis B—B.

The first axis A—A is spaced from the second axis B—B by a thirddistance and the third axis C—C is spaced from the fourth axis D—D by afourth distance. In one embodiment, the third and fourth distances areunequal; in another embodiment the third distance is greater than thesecond distance. In one embodiment, a line connecting the first axis A—Aand the third axis C—C is non-parallel to a line connecting the secondaxis B—B and the fourth axis D—D when the retractable vehicle step 720is in the retracted and/or deployed position. In one embodiment, theline connecting the first axis A—A and the third axis C—C is angularlydisplaced from vertical by a smaller angle than is the line connectingthe second axis B—B and the fourth axis D—D, when the retractablevehicle step 720 is in the deployed position.

The upper portion of the front arm 730 a is bent rearward and the lowerportion of the rear arm 730 b is bent forward to facilitate a wide rangeof motion of the arms and step member while permitting the arm(s) to bemade relatively thick and strong. With a greater range of motion thusimparted to the arms 730 a, 730 b and step member 722, the member 722can extend farther from the vehicle when deployed and retract furtherinto the vehicle for improved concealment. In addition, the bent arm(s)permit the location of the upper and lower axis pairs A—A, B—B and C—C,D—D relatively close to each other without the need to employ arms whichare unduly thin and weak.

The embodiment shown in FIGS. 18–19 is also particularly suited for usein the narrow space depicted, between the lower part of the verticalunderbody portion 16 which is located upward of an adjacent vehicleframe member 23. With little room to retract rearward, the stepping deck724 instead rotates primarily upward when retracting. Thus, in thedepicted embodiment the front edge 724 a of the stepping deck 724 islocated above the first axis A—A when the step member 722 is in theretracted position A.

When retracted, the retractable vehicle step 720 is substantiallyconcealed from the view of an observer standing next to the vehicle,because the lower surface 724 d of the stepping deck 724 extends inwardand downward from the lower edge of the exterior 14 at an angle ε ofabout 35–55 degrees with respect to vertical. While not as thoroughlyconcealed as other embodiments, the “upward” position of the retracteddeck 724 also blocks a significant portion of the arms, frame, etc. fromthe view of a typical vehicle-side observer. The concealment may befurther enhanced by painting or otherwise coloring the lower surface 724d of the stepping deck with a dark color (black, dark gray, etc.) orcoloring it to match the surrounding underbody, frame, etc.

FIGS. 20 and 21 depict another embodiment of the retractable vehiclestep 820, which may be similar to the embodiments discussed above exceptas disclosed below. The retractable step 820 comprises a stepping member822 that includes a stepping deck 824 bolted or otherwise rigidlyconnected to a support bracket 826. Front and rear support arms 830 a,830 b are rotatably connected to the support bracket 826 via pins 832 a,832 b. A rigid frame 834, which may be configured as necessary forconnection to the vertical underbody portion 16 (or frame member 23),provides a secure mounting for the support arms 830 a, 830 b which arerotatably mounted to the frame 834 via pins 836 a, 836 b.

The frame 834 may be fixed to the vertical underbody portion 16 (orframe member 23) via bolting, riveting, welding or other conventionalmethods. It will be appreciated, however, that a wide variety ofstructure may be used in place of or in addition to the frame 834 tofacilitate attachment of the arms 830 a, 830 b to the vehicle, or todifferent vehicle makes and models.

As with the embodiments discussed above, the retractable vehicle step820 shown in FIGS. 20–21 defines a set of first through fourth axes A—Athrough D—D corresponding to the previously-discussed sets of axes. Forthe sake of clarity, the distances between the various axes A—A throughD—D are not marked on FIGS. 20–21; however, the following discussion ofthe geometry of the layout of the axes applies with equal force to theembodiment of FIGS. 20–21, as it did with regard to the embodimentsdiscussed above. With reference to FIG. 20, the first axis A—A is spacedfrom the third axis C—C by a first distance and the second axis B—B isspaced from the fourth axis D—D by a second distance. In one embodiment,the first and second distances are unequal; in another embodiment thefirst distance is greater than the second distance.

The first axis A—A is spaced from the second axis B—B by a thirddistance and the third axis C—C is spaced from the fourth axis D—D by afourth distance. In one embodiment, the third and fourth distances areunequal; in another embodiment the third distance is greater than thesecond distance. In one embodiment, a line connecting the first axis A—Aand the third axis C—C is non-parallel to a line connecting the secondaxis B—B and the fourth axis D—D when the retractable vehicle step 820is in the retracted and/or deployed position. In one embodiment, theline connecting the first axis A—A and the third axis C—C is angularlydisplaced from vertical by a smaller angle than is the line connectingthe second axis B—B and the fourth axis D—D, when the retractablevehicle step 820 is in the deployed position.

The arms 830 a, 830 b to facilitate an extremely wide range of motion ofthe arms and step member while permitting the arm(s) to be maderelatively thick and strong. With a greater range of motion thusimparted to the arms 830 a, 830 b and step member 822, the member 822can extend farther from the vehicle when deployed and retract furtherinto the vehicle for improved concealment.

In the depicted embodiment, the arms 830 a, 830 b are bent to such adegree that, when the step member 822 is in the retracted position A, aline connecting the first and third axes A—A, C—C will intersect aportion of the rear arm 830 b near the second axis B—B, and/or a lineconnecting the second and fourth axes B—B, D—D will intersect a portionof the front arm 830 a near the third axis C—C. As a result, one or bothof the third and fourth axes C—C, D—D is situated above the first axisA—A when the step member 822 is in the retracted position A.

The retractable step 820 shown in FIGS. 20–21 thus has a wide range ofmotion, such that the entirety of the stepping deck 824 is locatedoutboard of the first axis A—A when the step member is in the deployedposition B and at least a portion of the stepping deck 824 is locatedinboard of the second axis B—B when the step member is in the retractedposition A.

In one embodiment, the rear arm 830 b forms a stop surface 833 near thethird axis C—C. The stop surface 833 is configured so that, when thestep member 822 is in the deployed position B, the stop surface 833 isthe forward-most portion of the rear arm 830 b. Thus, the stop surface833 contacts the rear surface of the front arm 830 a, preventing thearm(s) from rotating past the deployed position A. As detailed above,once in the deployed position A, a load placed on the stepping deck 824(or even the weight of the retractable step alone) will increase theforce pressing the stop surface 833 against the front arm 830 a. Theretractable step thus remains firmly “locked” in the deployed positionunder the applied load, and no torque reaction is transmitted to anydrive system connected to the arms 830 a, 830 b.

In the illustrated embodiment, the stop surface 833 has a flattenedconfiguration which contacts a similarly flat portion of the rearsurface of the front arm 830 a, when the step member 822 is in thedeployed position B. In other embodiments, a rounded shape or any othersuitable shape may be employed.

The stop surface 833, as well as the stop 52/152 and deployment stop 231b, may be considered a “static stop member.” As used herein, the term“static stop member” refers to any member which prevents movement of theretractable vehicle step beyond the deployed position B, by coming intocontact with a moving portion (such as one of the arms) of theretractable vehicle step and is either (i) fixed and substantiallyimmobile with respect to the vehicle (e.g., the stop 52/152) or (ii)fixed to or integrally formed with one of the arms or the step member(e.g., the deployment stop 231 b, intermediate portion 545/645 or stopsurface 833). As discussed in detail above, when a static stop member isused with various configurations of the retractable vehicle step, thestep can be maintained in the deployed position B simply by the weightof the retractable step itself (and any load placed on the steppingdeck) without need for complex, unreliable lockouts, toggles,spring-loaded catches, etc., and without transmitting a torque reactionto any drive system connected to the arm(s) of the retractable step. Inother words, the static stop member, arms and step member are sufficientto maintain the stepping deck in the deployed position upon movement ofthe retractable step thereto.

In this sense, where contact between two arms of the retractable stepprevents movement of the step beyond the deployed position, either orboth of the contacting portions may be considered a static stop member.It is contemplated that any of the static stop members disclosed hereinmay be employed with any of the embodiments of the retractable stepdisclosed herein.

FIGS. 22–26 depict another embodiment of the retractable vehicle step920, which may be similar to the embodiments discussed above except asdisclosed below. The retractable step 920 comprises a stepping member922 that includes a stepping deck 924 bolted or otherwise rigidlyconnected to a support bracket 926. Front and rear support arms 930 a,930 b are rotatably connected to the support bracket 926 via pins 932 a,932 b. A rigid frame 934, which may be configured as necessary forconnection to the vertical underbody portion 16, provides a securemounting for the support arms 930 a, 930 b which are rotatably mountedto the frame 934 via pins 936 a, 936 b. The stepping deck 924 defines agenerally flat upper stepping surface 924 c.

The frame 934 may be fixed to the vertical underbody portion 16 viabolting, riveting, welding or other conventional methods. It will beappreciated, however, that while the frame 934 is preferred, a widevariety of structure may be used in place of or in addition to the frame934 to facilitate attachment of the arms 930 a, 930 b to the vehicle, orto different vehicle makes and models.

As with the embodiments discussed above, the retractable vehicle step920 shown in FIG. 22 defines a set of first through fourth axes A—Athrough D—D corresponding to the previously-discussed sets of axes. Forthe sake of clarity, the distances between the various axes A—A throughD—D are not marked on FIGS. 20–21; however, the following discussion ofthe geometry of the layout of the axes applies with equal force to theembodiment of FIG. 22, as it did with regard to the embodimentsdiscussed above. With reference to FIG. 22, the first axis A—A is spacedfrom the third axis C—C by a first distance and the second axis B—B isspaced from the fourth axis D—D by a second distance. In one embodiment,the first and second distances are unequal; in another embodiment thefirst distance is greater than the second distance.

The first axis A—A is spaced from the second axis B—B by a thirddistance and the third axis C—C is spaced from the fourth axis D—D by afourth distance. In one embodiment, the third and fourth distances areunequal; in another embodiment the third distance is greater than thesecond distance. In one embodiment, a first line E—E connecting thefirst axis A—A and the third axis C—C is non-parallel to a second lineF—F connecting the second axis B—B and the fourth axis D—D when theretractable vehicle step 920 is in the retracted and/or deployedposition. In one embodiment, the first line E—E connecting the firstaxis A—A and the third axis C—C is angularly displaced from vertical bya smaller angle than is the second line F—F connecting the second axisB—B and the fourth axis D—D, when the retractable vehicle step 920 is inthe deployed position.

The first line E—E intersects the second line F—F at an instantaneouscenter of rotation ICR of the step member 922. The ICR marks theinstantaneous position of the pivot axis about which the step member 922would rotate if the arms 930 a, 930 b were to rotate from their presentpositions about the first and second axes A—A, B—B.

The retractable step 920 shown in FIG. 22 is configured to maintain theretracted position A, even upon placement of a heavy load on thestepping deck 924, without need for a separate locking system or inputfrom a drive mechanism or motor. In other words, the retractable step920 is “self-energizing” when in the retracted position A. When the stepmember 922 is in the retracted position A, the arms 930 a, 930 b areconfigured so that the instantaneous center of rotation ICR is locatedat, or inboard of, the upper stepping surface 924 c of the stepping deck924. (This is illustrated as zones 960, 962, 964, 966, 968 in FIG. 22A.)This in turn dictates that when the step member 922 moves toward thedeployed position, the initial motion from the retracted position A ofat least a portion of the upper surface 924 c of the stepping deck 924is upward (or has an upward component), after which the step member 922and upper stepping surface 924 c travel generally downward (or downwardand outboard) to the deployed position B. When the step member 922 is inthe retracted position, placement of a load on the upper steppingsurface 924 c thus urges the step member toward the retracted position,but further movement in that direction is prevented by the contactbetween the arms 930 a, 930 b. Consequently, the step member 922 cansupport heavy loads placed on the upper stepping surface 924 c when inthe retracted position, without need for a separate locking system, etc.

More generally, the retractable step 920 is self-energizing in theretracted position A, when the arms 930 a, 930 b are arranged so thatthe instantaneous center of rotation ICR is located (along aninboard-outboard axis) at, or anywhere inboard of, a load W applied tothe step member 922. (The load W is depicted herein as a point load; itshould be understood that references herein to the location of a load onthe step member 922 mean the point-load representation of anydistributed load (such as part of a user's weight transmitted through afoot placed on the upper stepping surface 924 c) that is applied to thestep member.) It has been found that while arranging the retractedpositions of the arms 930 a, 930 b to place the instantaneous center ofrotation ICR as far inboard as possible maximizes the self-energizingproperties of the retractable step, locating the instantaneous center ofrotation ICR too far inboard decreases the range of motion of theretractable step by requiring a sub-optimal arrangement of the arms 930a, 930 b when retracted. Consequently, in one embodiment, the arms 930a, 930 b are arranged to locate the instantaneous center of rotation ICRat, or slightly inboard of, the inboard quarter, half or two-thirds ofthe upper stepping surface 924 c of the stepping deck 924 (zone 959,960, or the sum of zones 960 and 962 in FIG. 22A). In anotherembodiment, the instantaneous center of rotation ICR is located at, orslightly inboard of, the entire extent of the upper stepping surface 924c of the stepping deck 924 (the sum of zones 960, 962 and 964 in FIG.22A).

In still other embodiments, when the retractable step 920 is in theretracted position the instantaneous center of rotation ICR is locatedfurther inboard, i.e. in zone 966 extending outboard from the first axisA—A to a location somewhat inboard of the upper stepping surface 924 c,or in zone 968, which is anywhere inboard of the first axis A—A.However, with the center ICR located in either of these zones the rangeof motion of the retractable step may be diminished as discussed above.In yet another embodiment, the center ICR may be located in zone 970,between the outboard edge of the step member 922/stepping deck 924 andthe outboard edge of the upper stepping surface 924 c. However, with thecenter ICR located in zone 970, the step may be self-energizing only ifthe load W is applied near the extreme outboard edge of the step member922.

In following good engineering practice, it may be desirable to arrangethe retracted positions of the arms 930 a, 930 b to place theinstantaneous center of rotation ICR at or inboard of a step regionwhich is defined as the entire portion of the step member 922 upon whicha user is likely to step. In one embodiment, the step region maycomprise the entire stepping deck 924 plus that portion of the supportbracket 926 which is adjacent to the inboard edge of the stepping deck924. This step region would encompass the sum of zones 960, 962, 964 and970 depicted in FIG. 22A. In one embodiment, the step region maycomprise the entire upper stepping surface 924 c plus that portion ofthe support bracket 926 which is adjacent to the inboard edge of thestepping deck 924. This step region would encompass the sum of zones960, 962 and 964 depicted in FIG. 22A. In another embodiment, the stepregion may comprise the entire stepping deck 924 plus substantially allof that portion of the support bracket 926 which protrudes from thevehicle. This step region would encompass the sum of zones 960, 962,964, 966 and 970 depicted in FIG. 22A. Finally, whether the steppingdeck is formed as part of a rail 925 (see further discussion below), oras a “plain” flat member like those disclosed above, the step region maycomprise anywhere that a user is likely to set foot upon the step member922.

In light of the above-described properties of the retractable step 920,the step region/stepping deck follows a unique deployment path whenmoving from the retracted position A to the deployed position B. Thedeployment path is characterized by an initial upward component UC (seeFIG. 22) which may be only a component of an overall initial motion IM.After first moving (from the retracted position A) in the direction ofthe initial upward component UC or initial motion IM, the stepregion/stepping deck moves generally downward and outboard to thedeployed position B.

Because the retractable step 920 possesses self-energizing propertieswhen in the retracted position, the step 920 is suitable for providingrunning board when retracted, and a convenient step when deployed. Tothis end, the upper stepping surface 924 c may be formed as part of arail 925 which serves as a running board when retracted (see FIG. 24),having a retracted position relatively close to, and just outboard of,the vehicle doors. When deployed, the rail 925 is rotated downwardsomewhat, so that the upper stepping surface 924 c takes on asubstantially horizontal orientation (see FIGS. 23, 25). Advantageously,the generally tubular form of the rail 925 may prevail at the front andrear ends thereof, to provide an “off-road” look when the rail 925 isretracted and serving as a running board. Again, the upper steppingsurface 924 c is formed in the rail 925, and reaches a convenienthorizontal position when the rail is extended to serve as a step. Asseen in FIG. 25, the rail 925 may be made wide enough to serve as arunning board or step for persons desiring to enter either of twoadjacent doors of the vehicle; in this case the upper stepping surface924 c may be formed as two separate flattened portions of the rail 925.In other embodiments a “plain” flat deck, board or other member may beused in place of the rail 925.

However, regardless of the precise structure employed, the rail, board,etc. may be mounted on two or more retraction assemblies 950 whichprovide retraction and deployment therefor. Each of the retractionassemblies 950 may comprise structure which generally similar to any ofthe embodiments disclosed herein for the retractable vehicle step;however, the embodiment shown in FIGS. 24 and 25 utilizes the mechanismdisclosed above in connection with FIGS. 22–23. One or both of theassemblies 950 may include a motor for moving the step between theretracted position (FIG. 24) and the deployed position (FIG. 25).

FIG. 26 is a schematic depiction of an overall retractable step system1000 according to which any of the embodiments disclosed herein may beimplemented. Control inputs are received by a sensor system 1002 andsent to an electronic controller 1004 for processing. The controlinputs, such as commands to extend, retract or stop the retractablestep, may be generated by a remote control 1006, and/or a vehicleignition switch, switches in the vehicle doors or door handles, ananti-pinch/anti-strike system, limit switches at the extremes of therange of motion of the retractable step, a timer, etc. The controller1004 processes the control inputs and passes an appropriate power signalto a motor 1006, which turns in the appropriate direction for extensionor retraction of the retractable step. The motor 1006, acting through acoupling 1008 (which may comprise a torque limiter and/or appropriategear system as discussed above), causes the linkage 1010 (e.g. the armsand step member) to move toward the extended or retracted position asneeded.

Although this invention has been disclosed in the context of certainpreferred embodiments and examples, it will be understood by thoseskilled in the art that the present invention extends beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses of the invention and obvious modifications and equivalentsthereof. Thus, it is intended that the scope of the present inventionherein disclosed should not be limited by the particular disclosedembodiments described above, but should be determined only by a fairreading of the claims that follow.

1. A retractable vehicle step assist, comprising: a first unitarysupport arm defining an inboard surface and an outboard surface, amaximum distance between said inboard surface and said outboard surfacedefining a first thickness, said first arm defining a substantiallyvertical first side and a substantially vertical second side, a maximumdistance between said first side and said second side defining a firstwidth, said first width being substantially greater than said firstthickness; a second unitary support arm defining an inboard surface andan outboard surface, a maximum distance between said inboard surface andsaid outboard surface defining a second thickness, said second armdefining a substantially vertical first side and a substantiallyvertical second side, a maximum distance between said first side andsaid second side defining a second width, said second width beingsubstantially greater than said second thickness; said first support armand said second support arm connectable with respect to an underside ofa vehicle so as to be pivotable about a first axis oriented generallyparallel to the ground and a second axis oriented generally parallel tothe ground, respectively; a static stop member located within a range ofmotion of one of said first support arm and said second support arm; anda step member having a support bracket and a stepping deck rigidlyconnected to said support bracket, said stepping deck having an uppersurface, said first support arm and said second support arm connected tosaid support bracket opposite said stepping deck so that said firstsupport arm and said second support arm are pivotable with respect tosaid step member about a third axis and a fourth axis, respectively,said fourth axis located inboard from said third axis; wherein saidfirst axis is spaced from said third axis by a first distance, saidsecond axis is spaced from said fourth axis by a second distance, saidfirst axis is spaced from said second axis by a third distance, and saidthird axis is spaced from said fourth axis by a fourth distance, as saidstep assist is viewed in a plane perpendicular to said first axis, andsaid third distance and said fourth distance are unequal; said firstsupport arm and said second support arm allowing said step member andsaid stepping deck to move between a retracted position and a deployedposition downward and outboard from said retracted position; wherein,when said step member is in said deployed position, said support bracketextends inboard and upward from said stepping deck and said uppersurface of said stepping deck is the uppermost portion of said stepmember outboard of said support bracket; wherein the entirety of saidstepping deck is located outboard of said first axis when said stepmember is in said deployed position and at least a portion of saidstepping deck is located inboard of said second axis when said stepmember is in said retracted position; wherein said static stop member,said first support arm, said second support arm and said step member aresufficient to maintain said stepping deck in said deployed position whena user steps onto said stepping deck.